Heat pump invoice template UK (2026): ASHP, CIS and VAT

A heat pump invoice has to explain what was surveyed, designed, first-fixed, installed, commissioned and handed over - not a vague "heat pump fitted" line. "Supply and install ASHP as agreed" does not tell a householder whether they got an air-source outdoor unit with a new cylinder and controls, a ground-source loop and indoor plant, a water-source package, radiator upgrades or underfloor as part of the same job, or electrics and making-good. It does not tell a main contractor's QS which plot, purchase order or M&E package to release. It does not tell a CIS contractor how much is labour and how much is the direct cost of the outdoor unit, cylinder, pipework, ground loop materials, radiators and controls you paid for.

Heat pumps are heating-system work, not a boiler swap brochure and not a full extension or orangery build. Mentions of a plumber, gas engineer, electrician or builder on this page are contrasts and cross-links - the subject here is the heat pump package (ASHP, GSHP or WSHP) with the pipework, emitters and controls that make it a working system. Soft landscaping or decking alone belongs elsewhere; keep planting and deck boards out of a heat-pump-only invoice unless they were part of the agreed package.

Who pays matters. Billing a private householder for a heat pump on their own home: normal invoice, no CIS. Billing a main contractor, developer or refurbishment principal for construction operations that include installing a heating system: often CIS. HMRC's CISR14090 is the lead reference for heat pump and heating-system work: Finance Act 2004 section 74(2)(c) covers installation of systems of heating (and other building services). Soften absolute claims - the facts of the contract matter. Under that manual, installation of a heating system is typically within scope when a contractor pays you; repair, maintenance, alteration or extension of an existing heating system is generally outside CIS; replacing a boiler as a component of an existing system can fall outside; a complete system replacement or a new install is in. When GSHP groundworks, trenches, boreholes or making-good sit in a preparatory or finishing package, CISR14240 can also be relevant. Soften if you only supply units with no install - CISR14220 keeps manufacture/delivery of building components alone outside CIS. Supply-plus-install can pull the whole payment into CIS (CISR14020 / CISR14030). Related fabric work (plant-room walls, floor openings) may still need a look under CISR14100, but for the heat pump itself lead with CISR14090. Private householders are not CIS contractors - see the public CIS overview.

VAT is different from decking and many other trade pages. For qualifying residential (and relevant charitable) installs of air-source, ground-source or water-source heat pumps, VAT Notice 708/6 sets a zero rate from 1 May 2023 to 31 March 2027 (then the treatment reverts toward the 5% reduced rate under the notice's framework - check the live notice nearer the time). Soften: the installer must meet the notice conditions; InvoiceAdept does not decide VAT status. Supply without install is usually standard-rated. Central heating where the heat pump is the principal element can be treated as a single zero-rated supply in the notice's worked examples (see Notice 708/6 example 3) when conditions are met. Never invent 0% for commercial, hospital or hotel installs that fall outside residential/charitable scope. Never reverse-charge a householder. Domestic reverse charge does not apply to zero-rated supplies.

This guide gives copy-paste fields, a labour/materials split for heat pump packages (including deposits before ordering units), stages from survey/design through first fix, unit install/commission and snag/handover, four worked examples and a practical treatment of CIS, VAT Notice 708/6 and domestic reverse charge. Figures are illustrative only, not UK market rates or a price list. InvoiceAdept does not decide CIS or VAT status and does not file CIS300, VAT returns, Making Tax Digital updates or Self Assessment to HMRC. It does not issue MCS certificates, Building Control certificates or Boiler Upgrade Scheme (BUS) grant paperwork.

Related templates: plumber, gas engineer, electrician, builder, deposit invoice, domestic reverse charge, how to invoice a UK client as a tradesperson and late payment rights. This page focuses on residential heat pump packages - ASHP outdoor unit plus indoor cylinder/controls, GSHP ground loops/boreholes, WSHP where relevant, radiator upgrades / underfloor as package lines, and electrics - not a stand-alone gas boiler swap as the main product.

Rules and links were checked for this guide on 7 September 2026. General information only, not tax, legal, Building Regulations, MCS, F-gas or grant advice. InvoiceAdept is from Tech Me Today Ltd, Companies House 15917255, ICO ZB944663.

In short

Start by identifying who pays you, which heat pump type you supplied or installed (ASHP / GSHP / WSHP), whether the job is a new system install or work on an existing heating system, whether units must be ordered before work starts, and whether the contract is supply-only or supply-and-install.

Private householder, own-home heat pump install: no CIS. The householder is not a CIS contractor. If VAT-registered and the install qualifies under Notice 708/6 for residential (or relevant charitable) energy-saving materials / heat pumps, the zero rate can apply from 1 May 2023 to 31 March 2027 when notice conditions are met - then check the live notice for the post-March 2027 position (framework points back toward 5%). Show survey/design, first-fix pipe/electrics/groundworks, outdoor unit, cylinder/controls, emitters, commission, snag and any BUS voucher narrative clearly. Do not invent 0% for a commercial plant room outside scope. Never reverse-charge a householder.

Heat pump package for a CIS contractor: typically within CIS when a contractor pays you for installation of a heating system (CISR14090). Soften: repair/maintenance/alteration/extension of an existing heating system is generally outside; component boiler swaps can be outside; complete system replacement / new install is in. Cite CISR14240 when GSHP groundworks or making-good sit inside a preparatory or finishing package. Split labour from materials at direct cost (CISR15060 / CISR15090). For heat pump units and cylinders purchased complete, materials are usually the purchase cost; labour is the install, pipework, electrics and commission.

Manufacture and delivery of units only (no install): generally outside CIS (CISR14220). A mixed contract that supplies the unit and includes installation can pull the whole contract into CIS (CISR14020 / CISR14030).

VAT zero rate (Notice 708/6): only when residential/charitable and notice conditions are actually met, for the window to 31 March 2027. Supply-only is usually standard-rated. Never reverse-charge a householder. Domestic reverse charge does not apply to zero-rated supplies.

Take a deposit before ordering heat pump outdoor units, cylinders or GSHP loop materials if your terms require one. Number and invoice that deposit. Then use recognisable stages: survey/design, first fix, unit install/commission, snag/handover. Keep variations for extra radiators, underfloor zones or buffer tanks separate from the agreed package.

Use the invoice generator for a first invoice. InvoiceAdept Free is £0 for five invoices per month. Pro is £7.99 excl VAT and includes WhatsApp send. Pro+ is £12.99 excl VAT and includes CIS. Stripe's own fees apply (UK cards 1.5%+20p), but InvoiceAdept adds no platform fee.

Who this heat pump invoice template is for

This template is for UK heat pump installers, heating engineers, plumbers and M&E subcontractors who deliver ASHP, GSHP or WSHP packages as a defined product, and for builders who include heat pumps in residential packages and need readable invoices for householders, landlords, contractors and housing clients. It covers the paperwork pattern, not a price list and not an MCS, Building Control or BUS document.

• Heat pump installers (air-source, ground-source, water-source)

• Heating engineers and plumbers who design and install heat pump systems as a defined package

• Gas engineers transitioning or running hybrid packages who still need clear heat-pump lines

• Electricians billing dedicated circuits, consumer-unit upgrades or controls as part of a package (or separately)

• Groundworkers trenching or drilling for GSHP loops as part of a heat pump package

• Builders who include heat pumps in residential packages alongside extensions or new plots

• Subcontractors to main contractors on residential heating / M&E packages

• Sole traders and limited companies who need CIS and VAT lines that match the payer

If your day job is a stand-alone gas boiler swap with no heat pump brief, a pure electrical rewire without a heat pump, or fabric-only building work, use those related guides and come back here for heat-pump-specific lines (outdoor unit, cylinder, ground loop, emitters, controls, commission and Notice 708/6 VAT notes).

Three heat pump jobs, three invoices

These three jobs can use similar kit but need different invoice logic.

A main contractor can be the CIS contractor even when the finished system serves a tenant or homeowner. If the builder engages you, your invoice is to that builder. That contractor-to-subcontractor payment is the one to test. If the householder hires and pays you directly, the householder invoice has no CIS.

What heat pump work belongs on the invoice

Name the work so a QS, householder or future buyer can see what was actually installed.

ASHP jobs need outdoor unit model/capacity, cylinder type and emitter scope on the description. GSHP jobs still need loop type (horizontal / borehole), array length or borehole count if quoted, and indoor plant. WSHP needs the water source arrangement as narrative. F-gas / refrigerant handling belongs in your compliance process - the invoice is not the F-gas register.

What a UK heat pump invoice must include

GOV.UK is narrower than most blogs. You must give a VAT invoice by law when both you and the customer are VAT-registered. If you are not registered, keep numbered records of what you charged - which is also how you get paid.

• A unique identification number

• Your name (or company name), address and contact information

• The customer's name and address

• A clear description of what you are charging for (address, ASHP/GSHP/WSHP, capacity, stage)

• The date the goods or service were provided (supply date) and the date of the invoice

• The amount being charged, the VAT amount if applicable (including 0% with the right narrative when Notice 708/6 applies), and the total amount owed

Sole trader with a trading name: show your own name and a serviceable address. Limited company: registered name, company number and registered office. The VAT registration threshold is £90,000, not the stale £85,000 figure. For a heat pump invoice, a clear description is what gets you paid, so name the site address, system type, approximate capacity, key plant (outdoor unit / cylinder / loop) and stage (deposit / first fix / install / completion).

CIS lines (UTR, labour, materials, rate, deduction, net payable) belong when a contractor is paying you under the scheme - not on a private householder job. Domestic reverse charge wording belongs only when the VAT reverse-charge tests are actually met between VAT-registered construction businesses on standard-rated supplies - never on a householder bill, and not on zero-rated Notice 708/6 lines. See domestic reverse charge.

Copy-paste heat pump invoice fields

Use these as a checklist when you raise the PDF or app invoice.

For the first invoice habit and field checklist, see how to invoice a client UK tradesperson. For deposits before ordering units, see the deposit invoice template.

Sole trader versus limited company

Do not invent a Ltd presentation if you are still a sole trader. Do not omit the company number on Ltd invoices when customers and accounts teams expect it.

Labour versus materials for heat pump CIS

On a householder invoice the split is courtesy and clarity. On a contractor invoice it is the CIS calculation when the work is in scope. Start with the gross, take off VAT, then take off the direct cost of materials you paid for. What is left is broadly the CIS base at 20%, 30% or 0% after verification.

Two habits cost money: one lump "heat pump £12,000" (CIS on the outdoor unit as well if you are under CIS) and stuffing mark-up into materials so CIS looks smaller. Heat pump units purchased as complete plant are usually materials at purchase cost; labour is the install and commission. Free-issue plant is not your material.

What heat pump job types to describe

Deposits and stages for multi-day heat pump jobs

A same-day minor control swap can be one invoice. An ASHP with cylinder, electrics and radiator upgrades - or a GSHP with groundworks - is not.

1. Deposit: before you order the outdoor unit, cylinder or GSHP loop materials. Invoice when you take it and state the percentage or fixed sum. See deposit invoice template. 2. Survey / design: heat loss, emitter schedule, electrical notes, siting and (for GSHP) loop design deliverables if billed as a stage. 3. First fix: pipe routes, electrics, groundworks/trenches/boreholes complete, ready for plant. 4. Unit install / commission: outdoor unit or ground array connected, indoor plant, emitters, flush, commission, user handover. 5. Snag / handover: agreed snags closed, balance less any agreed retention, plus variations approved in writing.

Retention is not a deposit. Deposit is money you take before or during. Retention is money held after completion against snagging. Show full value, retention withheld and release date, then invoice retention when it falls due. A deposit you receive is a VAT tax point for that amount on the day it lands if you are registered - apply the correct rate (including 0% when Notice 708/6 genuinely applies to that supply).

CIS: why heat pump installs are often within the scheme when contractor-paid

For contractor-paid work, start with CISR14090: installation of systems of heating (and other building services) under FA04/S74(2)(c). Soften absolute claims - the facts of the contract matter.

Key nuances from that manual (paraphrased carefully):

• Installation of a heating system is typically within CIS when a contractor pays you.

• Repair, maintenance, alteration or extension of an existing heating system is generally outside CIS.

• Replacing a boiler (or similar component) as part of an existing system can fall outside.

• A complete system replacement or a new install is in.

When GSHP trenches, boreholes, manifolds or making-good sit in a preparatory or finishing package, CISR14240 may also sit in the analysis. Related fabric openings or plant-room works can still touch CISR14100, but lead with CISR14090 for the heating system itself.

Rates after verification: 20% if registered net, 30% if not verified, 0% with gross payment status. Show UTR, labour, materials, rate, deduction and net payable. That printout is not a CIS300 - the contractor files it. InvoiceAdept does not file CIS300.

Deemed contractors (non-construction businesses) use a construction-spend test of more than £3 million in the 12 months since the first payment - not a £1 million myth. Mainstream construction businesses register when they pay subcontractors for construction work. See GOV.UK CIS.

VAT Notice 708/6: zero rate for qualifying heat pump installs

This is the section that differs most from decking and many other InvoiceAdept money pages. Read it slowly.

If you are not VAT-registered, do not charge VAT. If you are registered, check whether the supply is a qualifying install of energy-saving materials / heat pumps under VAT Notice 708/6.

Careful framing (always soften - InvoiceAdept does not decide VAT status):

• From 1 May 2023 to 31 March 2027, qualifying residential (and relevant charitable) installs of air-source, ground-source and water-source heat pumps can be zero-rated when notice conditions are met.

• After 31 March 2027, the notice framework points back toward the 5% reduced rate - check the live GOV.UK notice nearer the time rather than inventing a permanent 0%.

• Supply of heat pump equipment without installation is usually standard-rated.

• Where a heat pump is the principal element of a central heating system, Notice 708/6 example 3 supports treating the package as a single zero-rated supply when conditions are met - soften; match the notice, do not stretch it.

• Never invent 0% for commercial, hospital, hotel or other installs that fall outside residential/charitable scope.

• Never reverse-charge a householder.

• Domestic reverse charge does not apply to zero-rated supplies.

Never tell a commercial client their plant-room ASHP is "VAT free because heat pumps are zero-rated" without checking scope. Never reverse-charge a private individual.

Supply-only versus supply-and-install

If you quote supply-only and later add install under the same commercial relationship, revisit both CIS and VAT before the next invoice.

Domestic reverse charge note for contractor-paid heat pumps

Domestic reverse charge is a VAT rule between eligible VAT-registered construction businesses. It is not CIS and it is not a householder rule. When it applies to a standard-rated construction supply, you show VAT but the customer accounts for it - you do not collect the VAT as cash on that invoice. Full pattern: domestic reverse charge invoice UK.

Critical for heat pumps: if your residential install is correctly zero-rated under Notice 708/6, domestic reverse charge does not apply to that zero-rated supply. If the customer is a private householder, reverse charge does not apply anyway.

Worked examples A-D

Figures are ILLUSTRATIVE arithmetic only, not quotes, not UK average prices, not BUS grant amounts, and not a price list.

Example A - Householder ASHP on occupied home (no CIS, Notice 708/6 zero rate)

ILLUSTRATIVE. Assumes VAT-registered installer and a qualifying residential install meeting Notice 708/6 conditions within the 1 May 2023 to 31 March 2027 window.

If the install did not meet notice conditions, VAT would usually be standard-rated - do not force 0%.

Example B - Householder GSHP with deposit and stages (no CIS)

ILLUSTRATIVE. Householder; stages; VAT shown as 0% only as an illustrative Notice 708/6 assumption for a qualifying residential install.

Example C - Contractor-paid new ASHP install (verified 20% CIS)

ILLUSTRATIVE only. Verified subcontractor at 20%. Treat figures as VAT-exclusive for clarity. Assumes installation of a heating system (CISR14090 in scope), not a pure repair of an existing system.

Do not claim free-issue plant as materials. Do not shrink labour by stuffing mark-up into materials. Soften VAT on the contractor invoice separately - residential qualifying zero rate, commercial standard rate, or reverse charge only where tests are met on standard-rated lines.

Example D - Materials-only delivery (no install)

Mistakes that bounce heat pump invoices

Late payment: contractor debts are not consumer debts

Checked on 7 September 2026: Bank of England Bank Rate is 3.75% (held 30 July 2026; next MPC decision due 17 September 2026). For eligible business-to-business debts, statutory interest under the Late Payment of Commercial Debts framework is Bank Rate + 8% - currently 11.75% simple interest - plus fixed compensation of £40 / £70 / £100 per late invoice depending on debt size. Use the six-month reference date rule (rate in force on the preceding 31 December or 30 June). This statutory route does not automatically apply to private homeowners. See late payment rights and GOV.UK late commercial payments. InvoiceAdept does not file Money Claim Online or court claims.

How InvoiceAdept fits a heat pump installer

Operator: Tech Me Today Ltd, Companies House 15917255, ICO ZB944663. Start from the invoice generator or pricing.

FAQ

What should a UK heat pump invoice include?

Legal names and addresses, a unique number, dates, a description that names the site address, system type (ASHP/GSHP/WSHP), capacity, key plant and stage, quantities and rates, a due date and a way to pay. Split labour and materials on contractor jobs. VAT only if registered - including 0% with Notice 708/6 narrative when that genuinely applies. UTR and CIS only under a contractor, and only when CIS actually applies.

Do heat pump installers need a CIS invoice?

Only when a contractor is paying you for construction operations that are in scope. Lead with CISR14090 for heating-system installation. A homeowner job you sold yourself: no CIS. Soften for repair/maintenance of an existing system - often outside.

How do CIS deductions work on outdoor units, cylinders and loops?

CIS is on the labour / CIS base when the work is in scope. Units, cylinders, loop materials, pipe and radiators you paid for come off as materials at direct cost when evidenced. Rates are 20% verified, 30% unverified, 0% gross payment status. Mark-up is not a material. Free-issue is not your material.

Do I charge 0% VAT on every heat pump?

No. Qualifying residential (and relevant charitable) installs can be zero-rated under Notice 708/6 from 1 May 2023 to 31 March 2027 when conditions are met. Supply without install is usually standard-rated. Commercial installs outside scope should not be forced to 0%. InvoiceAdept does not decide VAT status.

Should I take a deposit before ordering the heat pump unit?

If your terms require it, yes - before you order outdoor units, cylinders or GSHP materials. Raise a numbered deposit invoice and credit it on later stages. See the deposit invoice template.

Is a boiler swap the same as a heat pump install for CIS?

Not always. CISR14090 distinguishes installation of a heating system (typically in) from repair/maintenance/alteration of an existing system and from replacing a boiler as a component (often out). Complete system replacement / new heat pump install is typically in when contractor-paid. Soften and test facts.

Does InvoiceAdept file CIS, VAT or Making Tax Digital to HMRC?

No. It raises the invoice, stores the record and on Pro+ prints CIS lines. It does not file CIS300, VAT returns or MTD quarterly updates. It does not issue MCS certificates, Building Control certificates or BUS grant paperwork.

What is the VAT registration threshold?

£90,000. Not £85,000.

What is the deemed CIS contractor construction-spend test?

More than £3 million on construction in the 12 months since the first payment for non-construction businesses - not £1 million. Mainstream construction contractors register when they pay subcontractors for construction work.

Can I reverse-charge a householder for a heat pump?

No. And reverse charge does not apply to zero-rated Notice 708/6 supplies either.

What payment terms should I use?

A practical residential default is 14 days from invoice date with a calendar due date. Commercial jobs follow the PO or contract. Put terms on the quote and the invoice.

Do I need MCS or Building Control on the invoice?

You can narrate that MCS certification, Building Control or BUS steps apply where relevant, but the invoice is not the certificate and not the grant form. Do not sell the PDF as statutory or scheme sign-off.

How should I invoice radiator upgrades or underfloor with the heat pump?

If emitters are in your package, show them as clear lines (labour and materials). If another trade invoices underfloor screed or finishes separately, do not pretend your heat pump invoice includes their whole package unless it does.

What if the main contractor free-issues the outdoor unit?

Invoice labour (and any materials you actually bought). Do not list free-issue plant as your materials for CIS.

Sole trader or limited company - does the template change?

Yes for the name block (personal name vs registered company name and number). CIS and VAT rules still follow the facts of the job and registration, not the template title.

Quote versus invoice on heat pump packages

A quote is the offer. An invoice is the request for payment for work done or a deposit due. Do not send a quote PDF labelled as an invoice when you want payment - accounts teams and householders need an invoice number, a due date and a tax point.

If the householder asks for a "receipt" after card payment, you can mark the invoice paid or issue a payment receipt - that is not a substitute for keeping the numbered invoice in your records.

MCS, Building Control and BUS - the invoice is not a certificate

Heat pump jobs often sit alongside MCS certification, Building Regulations notifications and Boiler Upgrade Scheme (BUS) vouchers or grants. Soften absolute claims here - scheme rules and local practice change, and grant amounts should be checked on current Ofgem / DESNZ publications rather than copied from a blog.

Keep certificates, vouchers and guarantee paperwork as separate attachments - the same habit as attaching a gas safety record to a boiler invoice rather than pretending the invoice is the record. Do not invent MCS statistics or current BUS grant figures on this page; check live Ofgem / DESNZ sources when you need numbers.

Variations that commonly appear on heat pump jobs

Price extras in writing before you install them. Then invoice them as coded variations so a dispute on one radiator run does not freeze the whole package.

Retention on contractor heat pump packages

Some main-contractor M&E packages hold a retention percentage until a defects date. If retention applies:

• Show the full stage value, the retention withheld, and the net payable now

• Diary the release date and raise a retention release invoice when due

• Do not call retention a deposit

• Do not assume householder jobs use retention - most do not

How to describe heat pump plant without sounding like a brochure

You do not need marketing copy. You need identifiers a QS can match to the quote.

Snagging and practical completion on heat pumps

Agree what "done" means before you ask for the final balance: system commissioned, hot water and heating demonstrated, controls explained, site left tidy, agreed snags listed. Photograph completion and keep commissioning records separate from the invoice. If a snag list remains, either hold a small agreed amount against those items or finish them before the final invoice - do not surprise a householder with a full balance while the outdoor unit still faults on defrost.

Checklist before you hit send

• Unique invoice number and calendar due date

• Correct legal customer (householder vs contractor Ltd name)

• Site address and PO/plot if commercial

• System type, capacity, key plant, emitters, stage

• Deposit credits shown with prior invoice numbers

• Labour/materials split if CIS applies

• No CIS and no reverse charge on private householders

• CIS tested against CISR14090 (install vs repair) when contractor-paid

• VAT treatment matches registration and Notice 708/6 facts (0% only when qualifying)

• No invented 0% on commercial out-of-scope jobs

• Bank details and/or card link

• UTR and CIS block only when required

• MCS / Building Control / BUS narrative not sold as a certificate

• Stripe UK cards 1.5%+20p if using card links; no InvoiceAdept platform fee

More worked detail: CIS materials evidence

When a contractor challenges your materials line, tickets win. Keep merchant or supplier invoices for outdoor units, cylinders, loop pipe, radiators and controls matched to the job address or PO. Round "about £7,000 materials" without evidence is how estimated deductions go against you. Van stock used on the job can sit in materials if you can show what it cost; guessing a round figure is weak.

More worked detail: householder communication channel

Domestic heat pump jobs are often sold in WhatsApp or email threads with photos of the plant cupboard and outdoor siting. Put the invoice in that same thread and keep the PDF numbered. Contractors still need email to accounts with the PO. Do not rely on a verbal "pay when the BUS comes through" after a five-figure plant order - grant timing is not your invoice due date unless your written terms say so.

About this guide

Written by InvoiceAdept Editorial for UK heat pump installers, heating engineers, plumbers, electricians and M&E subcontractors. Last reviewed 7 September 2026 against GOV.UK CIS pages (including CISR14090 as the lead heating-systems reference, plus CISR14220, CISR14240, CISR14020/14030, CISR15060/15090, and CISR14100 briefly for related fabric context), VAT Notice 708/6 (zero rate for qualifying residential/charitable heat pump installs from 1 May 2023 to 31 March 2027), VAT registration thresholds (£90,000), and Bank of England Bank Rate (3.75%, held 30 July 2026, next MPC 17 September 2026).

InvoiceAdept is invoicing software from Tech Me Today Ltd, Companies House 15917255, ICO ZB944663. Free: five invoices/month. Pro: £7.99 excl VAT. Pro+: £12.99 excl VAT with CIS lines. Stripe UK card fees apply (UK cards 1.5%+20p); InvoiceAdept adds no platform fee. InvoiceAdept does not decide CIS or VAT status and does not file CIS300, VAT returns, Making Tax Digital updates or Self Assessment. It does not issue MCS certificates, Building Control certificates or BUS grant paperwork.

Figures in examples are illustrative only. BUS grant amounts and MCS statistics are not invented here - check current Ofgem / DESNZ sources. This is general information, not tax, legal, Building Regulations, MCS, F-gas or grant advice.