The VAT reverse charge for builders and electricians: who pays, who doesn't, and the cash-flow hit nobody warned you about

A contractor I know took on a run of loft conversions for homeowners. He hired in a sparky and a plasterer as subbies, both VAT registered, same as him. When their invoices came in with no VAT on them and a line about a "reverse charge", he rang them up annoyed and told them to send proper invoices with the 20% on, because his customers were ordinary homeowners who weren't VAT registered, so as far as he was concerned he was the "end user" and normal VAT applied.

He was wrong, and it took an accountant a fair while to untangle it. The VAT status of his customers had nothing to do with it. He was buying construction services from his subbies and selling those services on as part of his own jobs. That makes him a contractor in the middle of a chain, not an end user. His subbies were right to leave the VAT off. He'd just spent a fortnight insisting they break the rules.

That exact mix-up is one of the most common in the trade, and VAT specialists see it constantly. If you do construction work for other VAT-registered businesses in the UK, the VAT domestic reverse charge almost certainly affects you, and getting it wrong cuts both ways: you either hand HMRC money you didn't owe, or you get an assessment for money you should have accounted for. This is the plain-English version I wish someone had sat me down with when I was running a small building firm. It isn't tax advice, an accountant is the person for that, but it's what I'd want a mate to actually understand before his next invoice goes out.

What the reverse charge actually is, in plain English

Since 1 March 2021, the way VAT moves through the construction chain changed. Normally, a supplier charges VAT, the customer pays it to them, and the supplier hands it to HMRC on their next return. The reverse charge flips that one step: for most construction work between VAT-registered businesses, the subbie no longer charges VAT. Instead, the customer (the contractor) records that VAT on their own VAT return, as both output tax and input tax, which usually cancels out to nothing actually paid.

Here's the part that catches people: it does not change how much VAT is ultimately due. It only changes who hands it over. Same tax, different person carrying it to HMRC.

The reason it exists is fraud. HMRC got tired of what it calls "missing trader" fraud, the vanishing tradesman who charges VAT on his invoices, collects it from the contractor, and then disappears before ever paying it on to HMRC. If the subbie never touches the VAT in the first place, there's nothing for him to vanish with. That's the whole logic. It's the same instinct behind CIS, where the contractor deducts the subbie's tax at source rather than trusting it'll get paid later. If you've read our guide to CIS for subbies, this is the VAT cousin of the same idea.

Does it even apply to you? The five gates

The reverse charge only kicks in when all five of these are true at the same time. If even one fails, you charge VAT the normal way.

• The work is a "specified service" under CIS. In practice that's most construction: building, altering, repairing, extending, demolition, civil engineering, painting and decorating, and installing things like heating, lighting, power and air conditioning.
• It's standard-rated (20%) or reduced-rated (5%) for VAT. Zero-rated work, like a lot of genuine new-build housing, sits outside the reverse charge.
• Both you and your customer are VAT registered. If your customer isn't VAT registered, you charge VAT normally.
• Both of you are registered for CIS.
• Your customer is not the end user, and hasn't told you in writing that they are. More on this next, because it's where most of the mistakes live.

A few things that trip people up even once they know the gates. The reverse charge applies to a job of any size, a £120 repair follows the same rule as a £400,000 contract. Your CIS payment status is irrelevant to it, gross payment status doesn't exempt you, the two schemes run independently. And it only applies to UK-to-UK supplies. One genuinely good bit of news: the value of your reverse charge sales does not count towards the VAT registration threshold (£90,000), so it won't tip a smaller business over the line on its own.

The end user rule, where it nearly always goes wrong

An end user is whoever is having the construction work done for themselves and isn't selling those construction services on to someone else. A homeowner having an extension. A shop fitting out its own premises. A developer building on its own land to sell or let the finished building. When you supply an end user, the reverse charge doesn't apply and you charge VAT normally.

The trap is in the middle of the chain. Go back to my contractor at the top. He thought "my customers are homeowners, so I'm dealing with end users, so I'm an end user too." That's the error. The VAT status of your customer's customer is none of your business. What matters is whether you are passing those construction services on. If you're a main contractor hiring subbies and then billing a client for the finished job, you're selling construction services on. You are not the end user, whoever your client happens to be.

There's a procedural bit that bites just as often. Since the rules were finalised, it's the customer's job to tell the supplier, in writing, that they're an end user. Until that written notification arrives, the supplier has to treat them as not an end user and apply the reverse charge. So as a subbie, your default is: no notification, no VAT. Don't take it off the invoice because someone said "I think I'm the end user" on the phone. Get it in writing or apply the charge.

The cash-flow hit that quietly sinks subbies

This is the bit that has nothing to do with paperwork and everything to do with your bank balance, and it's the part that genuinely hurt a lot of small subbies in 2021.

Before March 2021, picture a subbie invoicing £3,000 of labour plus £600 VAT. He'd receive the full £3,600. That £600 of VAT wasn't his to keep, but he didn't have to pay it to HMRC until his next return, anywhere from a few weeks to three months later. In the meantime it sat in his account as working capital. Buy materials, cover wages, smooth out a slow month. Every VAT-registered subbie in the country was quietly running on a rolling float of other people's VAT.

Under the reverse charge, that money never reaches your account at all. You invoice £3,000, you receive £3,000. The £600 goes straight onto the contractor's return.

Scale that up and it's serious. One way VAT specialists put it: if you do around £200,000 a year of reverse-charge work, you've lost roughly £40,000 of rolling working capital you used to have on tap. For a one-van operation that ran on that float without ever really clocking it, the change landed like a pay cut.

Two things soften it, and both are worth doing if this is you:

• Switch to monthly VAT returns. Once most of your sales carry no output VAT but you're still buying materials with VAT on them, you often end up in a permanent repayment position, HMRC owes you most quarters. Filing monthly instead of quarterly means those refunds come back roughly three times as often, which helps the cash flow no end.
• Check whether the Flat Rate Scheme still pays. Reverse charge sales are excluded from the Flat Rate Scheme, so for a lot of subbies the scheme stopped making sense overnight. If most of your work is now reverse charge, the flat rate maths may well have flipped against you. You can leave the scheme at any time, you don't have to wait for an anniversary.

What your invoice has to say

When the reverse charge applies, your invoice changes in a specific way. Get this wrong and you create a mess for both sides. A compliant reverse charge invoice:

• Charges no VAT in the total. The amount due is the net figure only.
• States clearly that the reverse charge applies. Wording like "Reverse charge: customer to account for VAT to HMRC" or "VAT domestic reverse charge applies".
• Still shows the VAT rate and the VAT amount, so the customer knows exactly how much to account for. You show it, you just don't add it to the total or collect it.
• Shows both VAT numbers, yours and the customer's.

The mistakes that earn you an HMRC bill

Most reverse charge trouble comes down to a handful of repeat offenders.

1. Splitting labour and materials to charge VAT on the materials

A common move: a subbie tries to put labour on one invoice with no VAT (reverse charge) and materials on a separate invoice with 20% VAT added, thinking materials are somehow outside it. They aren't. If the contract is for labour and materials together and the reverse charge applies to the labour, it applies to the whole supply, materials included. Splitting the paperwork doesn't split the VAT treatment. You'll just have issued an incorrect invoice.

2. Assuming end user status instead of getting it in writing

Covered above, but it's the single biggest one, so it's worth saying twice. No written end user notification means you apply the reverse charge. Don't take VAT off, or leave it on, based on a verbal "I reckon I'm the end user." The default position when in doubt is that the reverse charge applies.

3. Charging VAT when you shouldn't, then everyone reclaims it

Here's the nasty one, because it looks harmless. Say a subbie charges 20% VAT on a job that should have been reverse charge. The contractor pays it, then reclaims that VAT as input tax on their return. Meanwhile the subbie pays it over as output tax. On the surface, fine. But HMRC's view is that the VAT was never validly charged, so the contractor wasn't entitled to reclaim it. HMRC can assess the contractor and claw it back, leaving them to chase the subbie for a corrected invoice and a refund. Because the VAT amount sits right there on the invoice, this slips through accounting systems all the time and only surfaces in a review. It's a real, common source of assessments.

4. The 5% mercy rule, and not leaning on it

One bit of give in the system: if the reverse charge element would only make up 5% or less of the value of a whole supply, you're allowed to disregard it and apply normal VAT to the lot, to save splitting hairs on tiny amounts. It's a sensible safety valve. It is not a loophole to lean on for borderline jobs, and if you're regularly relying on it to dodge the charge, that's a conversation to have with your accountant before HMRC has it with you.

How Trade PA handles the reverse charge

Honest version: the reverse charge is exactly the kind of thing that's simple in principle and a nuisance in practice, because it's a per-client status you have to remember to apply correctly on every single invoice, with the right wording, the VAT shown but not totalled, both numbers on there. Miss it once and you've got one of the messes above.

So in Trade PA it works the way CIS does: you tell the app which of your clients are reverse charge customers, because you're the only one who knows whether a given contractor has given you end user notification or not. Once a client is set as reverse charge, every invoice Eve raises for them comes out compliant automatically: no VAT added to the total, the correct "customer to account for VAT to HMRC" wording, the rate and amount shown, both VAT numbers in place. You set the status once, the invoices come out right every time after that.

What it deliberately doesn't do is guess. It won't decide for you whether a customer is an end user, because that's a judgement only you can make and getting it wrong is your liability, not a piece of software's. The job of the app is to make sure that once you've made the call, the paperwork is never the thing that lets you down.

None of this changes the tax you owe. It changes who carries it to HMRC, what your invoice says, and how much working capital you've got to play with. Get the client status right, get the wording right, plan for the float that's gone, and the reverse charge stops being a thing that bites you and goes back to being background noise. As ever: this is the plain-English version, not formal advice. For your specific setup, especially the Flat Rate and monthly returns decisions, have the five-minute chat with your accountant. It's cheaper than the assessment.

For the official detail, HMRC's VAT reverse charge technical guide is the primary source, and the common pitfalls writeup in Tax Adviser is a good read on the real-world errors.

Trade PA