"Cash alright?" — why paying cash isn't the favour your customer thinks it is

The job's done, the customer's at the door, and out comes the folded wad. "Cash alright? Saves you the tax, eh?" — with a wink, like they've just done you a turn.

Every tradesperson has had this conversation. Most customers genuinely believe they're helping. So it's worth being clear-eyed about what's actually on offer — because it's usually not a favour, it's a transfer of risk. From them to you.

Cash is legal. The wink isn't.

There is nothing wrong with being paid in cash. Cash, bank transfer, card, cheque — HMRC doesn't care how the money arrives. It all counts as income, and it all goes on your Self Assessment the same way.

Which means declared cash is taxed exactly the same as a bank transfer. There is no version of "cash saves you the tax" that doesn't mean "don't declare this one." That's the favour being offered: an invitation to evade tax, where the customer gets the discount and you get the risk.

And the risk is real. There's no threshold below which cash jobs are tax-free — the £1,000 trading allowance covers your total self-employment income for the year, not a per-job free pass. If HMRC finds undeclared income, the penalty runs from 30% of the unpaid tax for careless errors to 100% for deliberate evasion, plus the tax itself, plus interest. A £300 job pocketed quietly can cost multiples of £300 years later.

What cash costs you even when you do declare it

Set the tax question aside entirely — declare every note, do it all properly — and cash is still the worst way to get paid:

• No trail when it matters. A bank transfer is its own receipt. Cash is "I paid him" versus "no you didn't", with no evidence either way. The rare dispute that goes properly wrong — a chargeback of trust, a small claims letter, an insurance question — is exactly the moment you want a payment record that isn't your word against theirs.
• It's income you can't prove. Mortgage applications, van finance, business loans — they all run on your declared, documented income. Undeclared cash makes your business look smaller precisely when you need it to look real. Plenty of traders have discovered at the mortgage broker's desk that years of "doing customers a favour" quietly cost them a house.
• The admin doesn't shrink, it grows. Cash still has to be counted, recorded, invoiced, and physically taken to a bank — and banks ask questions about regular cash deposits. A transfer lands in the account already recorded.

The "discount for cash" maths

If a customer wants 10% off for cash and you declare the income — as you must — you've given away 10% of the job in exchange for a trip to the bank. That's it. That's the deal.

The discount only makes sense in the undeclared version, and the undeclared version is the one with the penalties attached. If you want to reward good customers, discount something that genuinely saves you money — payment on the day, a repeat booking — not the payment method that costs you most.

What to say at the door

You don't need to accuse anyone of anything. A plain sentence does it:

"Bank transfer's easiest for me — the details are on the invoice. Or I can send you a card link."

Said flatly, it lands as routine, because it is. Most customers just want the easiest way to pay; give them one and the cash conversation never happens. Sending the invoice with a payment link the customer can pay from their phone — which is what grafter.ly does — makes card the path of least resistance for both of you.

One thing you can't do: add a surcharge for card. Card fees on consumer payments have been banned from being passed on since 2018. If the fee stings, price it into your rates like any other cost of doing business.

And if a customer will only pay cash, gets shifty about receiving an invoice, or pushes the wink a second time — that's information. The customer who wants no paper trail today is the customer you'll wish had one when something goes wrong later.

The bottom line

Take cash when it suits — it's legal, and sometimes it's simply what the customer has. Invoice it, bank it, declare it, and it's fine. But stop treating it as the favour. The payment method that actually does you a favour is the one that arrives recorded, provable, and already in the bank — and that's a transfer or a card link, every time.