None of this constitutes financial advice or guidance. Just my personal take, written for myself, and I don't guarantee its accuracy. Take independent financial advice for any of your own decisions.

You’re losing money if you don’t have a credit card that rewards you in some way (typically cash or airmiles).

Which is very straightforward for groceries and restaurants and so on.

What about HMRC bills?

If you try to pay those with a rewards credit card you’ll find you can’t: personal credit cards aren’t accepted.

But there’s a workaround.

There’s a card called Curve. It’s a debit card you can use anywhere and it proxies the payments to some other credit card you own.

This has a few benefits:

1. You can use it with merchants that only take debit cards, like HMRC
2. It can convert foreign currency purchases into your card’s currency before re-billing them, so you avoid currency conversion fees
3. You can use Apple Pay / Google Pay with cards that still don’t support it
4. You don’t have to carry all your cards—you can change which one Curve re-bills to in the app in real-time (or even after the fact)

This used to work with HMRC for free. More recently they’ve added charges/caps: if you take the £150/year Curve Metal card you can spend £10,000/month at HMRC. Let’s say you have the Virgin Atlantic Reward+ Mastercard: a £30k tax bill would earn 45,000 points, which I’d value at £450-£675.

If you have a limited company, ask your accountant whether they’re OK with you expensing company tax bills this way too.