In 2016 the government reversed the long-standing system of banks deducting basic-rate tax from interest before paying it out. Interest began to be paid gross, and the change was presented as simplification. In practice, it was a cheap way of making people feel a little better off at a time when interest rates were close to zero and the Personal Savings Allowance covered almost everyone. With negligible returns, there was little tax at stake and it suited the Treasury to give people the sense of tax-free growth without actually giving anything away.
That context no longer exists. Easy-access savings routinely pay four per cent or more, and fixed-term rates sit comfortably above that. When rates were near zero, a gross system was harmless; at today’s levels it creaks. A basic-rate taxpayer with £25,000 at four per cent already exceeds the Personal Savings Allowance. Higher-rate taxpayers have even less room before they hit their own limit, and additional-rate taxpayers never had an allowance at all. A framework designed for a low-interest world is still in place, and the result is predictable: many people now face unexpected tax bills and a requirement to use self-assessment that they do not anticipate.
The misunderstanding is widespread. For many savers, “gross” still reads as “tax-free”, and the messaging in 2016 helped to cement that assumption. Banks do not report interest consistently. Some issue statements as soon as the tax year ends; others take months. Many expect savers to calculate the interest themselves from account statements, which is reasonable in principle but unrealistic in practice when people hold several accounts, use joint arrangements, or move money between providers to chase higher rates. The system works only for those with a single account and stable balances.
The detailed rules do not help. Interest is taxable when it is received, and HMRC are clear that this applies even if it is left in the account. That surprises people. A one-year fixed bond might show no movement until maturity, but the interest may still be “received” for tax earlier if it is made available, even notionally. Interest on notice accounts, monthly-paying fixed terms, foreign-currency deposits and peer-to-peer platforms each have their own quirks. The rules themselves are not new, but they now produce meaningful tax liabilities rather than rounding errors.
Then there is the £10,000 rule, which very few people know about. Anyone with more than £10,000 of taxable savings income in a year must register for self-assessment, even if all the tax is eventually collected through adjusted PAYE. Many assume that HMRC will simply update their tax code, but this does not apply when interest goes above that level. It is easy to cross the threshold without realising, especially for people holding larger cash reserves for planned spending, downsizing, or short-term security. For years the rule was irrelevant. At current rates, it catches ordinary savers.
The environment has also challenged the old view that Cash ISAs were secondary to investment ISAs. When interest rates were trivial, the Personal Savings Allowance did most of the work and Cash ISAs were often dismissed as unnecessary. Today, the case for using Cash ISAs is stronger for a different reason. The issue is not that cash outperforms cautious portfolios; it is that the tax treatment of interest is far harsher than the tax treatment of investment returns. Interest is taxed at 20 per cent for basic-rate taxpayers, while dividends are 8.75 per cent and capital gains can be 18 per cent, with most people still having a £3,000 capital gains allowance they would not otherwise use. Different rules apply to different people, and advice is always needed, but the disparity in tax rates means taxable cash can be far less efficient than many assume.
My own view is that the simplest and most honest solution is to reintroduce basic-rate deduction at source. It worked for decades. Most savers are basic-rate taxpayers; for them, the matter would end there. Higher-rate taxpayers would still owe the top-up, but that is easier to handle than calculating the entire liability from scratch. Additional-rate taxpayers would have a smaller balancing payment. People with unused Personal Savings Allowance could reclaim the tax, which is administratively simpler than the current position where millions of people have to work out whether they owe anything at all.
This would not remove complexity entirely, but it would reduce the number of people falling into self-assessment simply because their savings produce a return again. It aligns better with how people think about money. A net figure feels like the amount that actually belongs to them; at the moment, many only learn months later that part of their “gross” interest never did.
There will be questions about administration, but banks operated deduction at source for decades. The mechanisms still exist, and the administrative burden on financial institutions is modest compared with the burden currently placed on ordinary savers. The issue is not whether the system can be operated; it is whether the current arrangement serves anyone well in a world of meaningful interest.
In my view it does not. Paying interest gross makes the system look cleaner than it is. It shifts compliance risk onto people who neither expect it nor benefit from it, and it encourages errors that can lead to penalties or unexpected tax bills. Reintroducing basic-rate deduction at source would not solve every issue, but it would bring the system back into line with the way people use cash today, and reduce the friction caused by a policy designed for a different world.
