Why a regular saver’s headline rate is not the interest you end up with

A regular saver is built for a habit rather than a lump sum. You agree to pay in a set amount each month, often between £25 and a few hundred pounds, usually for twelve months. In return the bank or building society offers a fixed rate that is often noticeably higher than its easy-access accounts. At the end of the term the account matures, and the money usually moves into an ordinary savings account at a lower rate.

Nothing about the advertised rate is misleading in itself. It is an annual rate, and the account pays it. The catch is simply arithmetic: for most of the year, much of your money has not been paid in yet.

How the interest is worked out

Interest on savings is calculated on the balance in the account, usually daily, and paid either monthly or at the end of the term. In a regular saver, the first deposit earns interest for twelve months, the second for eleven, and so on, until the last deposit earns interest for just one month. On average, each pound is in the account for only about half the year.

That is why the interest earned on a year of deposits is roughly half of what the same rate would earn on the full amount for a full year. The exact figure depends on the deposit dates and how the bank compounds, but the halving effect is the same everywhere.

Simple monthly calculation without intra-year compounding; real accounts may differ by a few pence. Rates are examples, not current offers.

Making a fair comparison

The question is not whether a regular saver “really” pays its rate. It does. The question is what the alternative would be for the same money.

If the money arrives monthly anyway, for example from salary or pension, a regular saver is a good way to put it to work, and the right comparison is with paying the same amounts into an easy-access account at its lower rate.

If you already have the £3,000, the comparison changes. Putting the whole sum in an easy-access or fixed-term account earns interest on all of it from day one. Many savers do both: the lump sum goes into an easy-access account, and £250 a month is moved from there into the regular saver. The money earns interest throughout, and the higher rate applies to a growing share of it.

Doing the sums

An illustrative case. Helen has £3,000 in an easy-access account paying an example 4.00%. Left alone for a year, it would earn about £120. Instead she moves £250 a month into a regular saver at 6.00%. The regular saver earns £97.50. The shrinking easy-access balance, which starts at £2,750 after the first transfer and falls by £250 a month, earns roughly £55. Together that is about £152, around £32 more than leaving it all in easy access. Illustrative figures only.

The small print that changes the result

• Missed or reduced payments. Some accounts allow a missed month to be made up later; others do not, or close the account.
• Withdrawals. Many regular savers allow no withdrawals before maturity, or only a limited number, sometimes with loss of interest.
• Linked accounts. The best rates are often reserved for customers who hold the provider’s current account.
• Fixed or variable. Some regular saver rates are fixed for the year; others can change.
• What happens at maturity. Most accounts move the money into a lower-paying account when the term ends. A note of the maturity date in the diary helps.

Tax on the interest

Regular savers held outside an ISA pay interest without tax deducted. Whether you owe tax depends on your other income and allowances. GOV.UK explains that most people have a Personal Savings Allowance, and some also have a starting rate for savings of up to £5,000 if their other taxable income is less than £17,570. Banks report the interest paid to HMRC after the end of each tax year, and HMRC adds together the interest from all your accounts. Some regular savers are offered as cash ISAs, in which case the interest is tax-free.

How safe the money is

Savings with UK banks, building societies and credit unions are protected by the Financial Services Compensation Scheme. The Bank of England explains that the limit rose from £85,000 to £120,000 per person, per authorised firm, on 1 December 2025. Brands that share one banking licence count as one firm, so it is worth checking which licence a savings brand sits under if your total savings with a group are large.

Who this matters for, and what to check

Regular savers suit people who can put aside a fixed amount from income each month and do not need instant access. They are also a gentle way to build a habit, for example in the years before retirement or when saving for a grandchild. Before opening one, check the minimum and maximum monthly amounts, whether payments must be made by standing order, the withdrawal rules, whether a linked current account is needed, and the rate and account the money moves into at maturity.

The short version

A regular saver pays its advertised rate, but on a balance that builds up over the year, so twelve months of deposits earn roughly half of what the same rate would earn on the whole sum for a year. In the example, 6.00% on £250 a month produces £97.50, or 3.25% of the £3,000 paid in. Compare it with what the same money would earn elsewhere, read the withdrawal and maturity rules, and note the date the term ends. For money set aside for decades rather than months, the more important number is often the yearly charge, as our piece on fund charges over twenty years shows.