Variation invoice template UK (2026): extras, change orders, CIS and VAT
Variation invoice UK, short answer: a variation / extras / change-order invoice bills agreed extras or variation orders that change the original quote or contract sum — not a named schedule stage, not an open % progress valuation, and not a deposit or retention release. Who pays is set by the contract (main contractor or client). CIS may apply when a CIS contractor pays you for construction operations — soften with HMRC’s CIS overview and your accountant. A private householder paying for work on their own home is usually not CIS and is never treated as the CIS contractor for that home. If you are VAT-registered (threshold £90,000), show VAT correctly on taxable lines; if you are not registered, do not charge VAT.
Use this page when the PDF is a variation / extras / change-order bill for work agreed after the original quote. Process how-to lives on the sister how to invoice variation orders and extras. It is not a named stage payment, not an open-ended progress payment, not a deposit, and not a retention release. Figures below are illustrative only. Need the PDF now? Open the free invoice generator (Free: 5 invoices; Pro £7.99 / Pro+ £12.99).
Who pays, CIS and VAT on a variation invoice
Start with who is paying the agreed extra and whether the variation is written into the contract sum. Variation billing is about change orders already agreed, not a CIS shortcut.
Who pays you | Typical variation job | CIS? | VAT if registered |
|---|---|---|---|
Private householder | Agreed extras on their own home (e.g. upgrade tiles, extra sockets) | Usually no — never treat them as CIS contractor for own home | Often 20% on ordinary domestic works — soften Notice 708; do not invent 0% |
Main contractor / CIS contractor | VO / change order against a construction contract | May be in CIS base when ops are in scope — soften with HMRC / accountant | Normal VAT, or reverse charge only when eligible contractor tests met — never on a householder |
Developer / client QS | Certified variation against contract sum | Depends whether the payer is a CIS contractor for construction ops | Show net / VAT / gross if registered |
Stage / progress (not this page) | Named schedule stage or open % progress on original scope | Same CIS tests — use stage or progress sisters | Same VAT rules |
CIS rates (0% / 20% / 30%) sit with the contractor when CIS applies — InvoiceAdept does not decide status and does not file CIS300. VAT threshold is £90,000. InvoiceAdept does not file VAT returns, MTD updates or Self Assessment.
Variation vs stage vs progress vs deposit vs retention
Use this page when the deal is an agreed extra / change order that changes the original quote or contract sum. Sister pages stay for sister intents.
Billing shape | When it fits | Invoice cue |
|---|---|---|
Variation / extras (this page) | Agreed change order or extras after the original quote | VO / change-order ref + description of extra + agreed sum |
Process steps: agree, write, then bill | Sister how-to — link from this PDF template | |
Named stage in an agreed payment schedule | Stage number + schedule label | |
Open-ended % or valued progress on original scope | % complete / cumulative to date | |
Upfront sum before (or as) work starts | Deposit % or fixed sum | |
Holdback previously deducted is now due | Retention % / amount, release trigger |
If the PDF is only a booking deposit, use deposit. If you are billing a named schedule stage of original scope, use stage. If you are releasing holdback, use retention. Do not invent CIS on a householder variation bill.
What a UK variation invoice must include
Field | Always? | Variation notes |
|---|---|---|
Your name or business name | Yes | Match Self Assessment / Companies House |
Your address and contact | Yes | Email helps QS / AP queries |
Customer name and address | Yes | Ltd = registered name; add site address if different |
Unique sequential invoice number | Yes | e.g. INV-VO-2026-0003 |
Invoice date | Yes | Date of issue |
Tax point / supply date | If VAT-registered and different | Useful when VO completion date differs from issue date |
Description of variation | Yes | Site, VO / change-order ref, what changed, agreed sum; “variation / extras — not stage payment” |
Original quote / contract / prior invoice refs | Strongly recommended | Link the original contract sum and any prior VO numbers |
Payment terms | Yes | Due on receipt / 7 / 14 / 30 days (or contract VO cycle) |
VAT number, rates, VAT amount | If VAT-registered | Show net, VAT and gross |
CIS UTR / deduction narrative | When a CIS contractor pays you within scope | Omit on true householder PDFs |
Bank details | Strongly recommended | Sort code and account name matching the invoice |
Never reverse-charge a private householder. Never invent CIS on a domestic own-home bill.
Copy-paste variation invoice example (illustrative)
Scenario: sole trader electrician invoices a main contractor for VO-03 — extra 12 sockets and cable run agreed after first fix on a commercial fit-out. CIS registered at 20%. Not VAT-registered. Agreed VO net = £1,250 (illustrative).
Line | Qty | Unit | Net |
|---|---|---|---|
VO-03 — extra 12 double sockets + cable run, Unit B, agreed 10 Sep 2026 | 1 | VO | £1,250.00 |
Original contract / Stage 2 first fix | Already billed — not re-billed here | ||
Gross subject to CIS (this variation) | £1,250.00 | ||
CIS deduction @ 20% | −£250.00 | ||
VAT | Not registered — net only | ||
Amount payable by contractor | £1,000.00 |
Narrate on the PDF: “VO-03 extras at [site] per written change order. Not a stage payment or retention release. CIS registered 20%. UTR on file.” Keep each VO separate so AP can match the change-order log.
CIS, VAT and reverse charge cues
Topic | Practical rule |
|---|---|
Variation for a CIS contractor on construction ops | May be in CIS base — soften |
Householder own-home extras | Usually no CIS; never treat them as CIS contractor |
VAT threshold | £90,000 |
Domestic reverse charge | Never on a householder; contractor tests only |
Deemed contractor | £3 million construction-spend framing — not £1 million |
Agree before you bill | Get the VO / extras in writing before issuing the PDF |
InvoiceAdept | Does not file CIS300, VAT, MTD or Self Assessment |
Agreeing extras before you invoice
Confirm scope, price, who authorises the change, and whether CIS will apply before you do the extra work. Put the change order in writing so the PDF can cite the same VO number.
Shape | How to show it on the PDF |
|---|---|
Fixed sum per VO | “VO-03 — extra sockets = £X agreed” |
Day-rate extras | “Extra labour 1.5 days @ £Y = £Z per agreed VO” |
Materials uplift | List materials net; keep separate from original materials lines |
VO then stage / final | This page for the VO; stage / final for original schedule scope |
Weak: “Extras as agreed £1,250.” Usable: “VO-03 — extra 12 double sockets + cable run Unit B agreed 10 Sep 2026 = £1,250 net, CIS 20%, not VAT-registered, not a stage payment.”
Payment terms and getting paid
Main-contractor VO bills often follow the same certificate / AP cycle as stages (14 or 30 days). Householders often prefer 7 days or due on receipt once the extras are done. Put bank details on the PDF. Soften B2B late-payment interest with the contract and your accountant.
Common mistakes on variation invoices
Mistake | Fix |
|---|---|
Vague “extras as agreed” lump | Name the VO / change-order ref, site, what changed and amount |
Billing extras without written agreement | Agree in writing first — see the how-to sister |
Calling a stage payment a variation | Use the stage sister for named schedule milestones |
Mixing VO lines into an open % progress bill | Keep VOs separate from progress valuations |
CIS narrative on a householder extras PDF | Remove CIS lines when the householder pays |
Charging VAT when not registered | Net only until registered |
Re-billing original scope as a “variation” | Only bill what changed the contract sum |
Reverse-charging a householder | Never — reverse charge is contractor-to-contractor when tests met |
Frequently asked questions
Is a variation invoice the same as a stage payment invoice?
No. A stage payment cites a named contractual stage from a payment schedule. A variation invoice bills agreed extras / change orders that change the original quote or contract sum.
How is this different from the how-to variation sister?
This page is the PDF template shape (fields, example, CIS/VAT cues). The how-to sister covers the process of agreeing and writing VOs before you bill.
Does CIS always apply to variation invoices?
No. CIS may apply when a CIS contractor pays you for construction operations. Private householders on their own home are usually outside CIS — soften with HMRC / your accountant.
Can I put CIS deduction lines on a householder variation invoice?
Usually no. If a private householder pays the extras on their own home, leave CIS narrative off the PDF.
What VAT threshold should I use in 2026?
£90,000. Soften registration with your accountant.
Should I wait until the end of the job to bill extras?
Often better to bill each agreed VO promptly so AP can match the change-order log — check your contract cycle.
Do I charge VAT on variations if I am not VAT-registered?
No. Net only until you are registered.
Where can I build the PDF quickly?
Use the InvoiceAdept free invoice generator — Free covers 5 invoices; Pro is £7.99 and Pro+ £12.99 when you need more.
Next step: build the variation invoice
Cite the VO / change-order ref, keep householder vs contractor facts straight, show CIS arithmetic only when due, and show VAT only if registered (£90,000 threshold). Open the free invoice generator, paste the lines from the worked example shape, and send when the extras are complete. InvoiceAdept does not file CIS300, VAT returns, MTD or Self Assessment for you.
Last reviewed: 17 September 2026.
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