What interest rate does the Tandem Bank 18 Month Fixed Saver pay?

The Tandem Bank 18 Month Fixed Saver pays 4.90% AER, fixed for 18 months.

How much interest could I earn?

Saving £10,000 for 18 months would earn about £744 at 4.90% AER. This assumes the rate stays the same and interest stays in the account.

Can I withdraw my money?

No. Your money is locked in until the fixed term ends, so only put in what you won't need before then.

When is interest paid?

Interest is paid on each anniversary of opening.

Who can open this account?

New and existing Tandem Bank customers can open it. You can open it online or in the app.

Is my money protected?

Yes. Eligible deposits are protected by the Financial Services Compensation Scheme (FSCS) up to £120,000 per person, per banking licence.

How does it compare with other 18-month fixed rate bonds?

At 4.90% AER it ranks 4th of 15 18-month fixed rate bonds we track. The best pays 5.12% and the average is 4.62%.

Dashboard

Fixed Rate

Tandem Bank 18 Month Fixed Saver Review

A competitive 18-month fixed rate bond from Tandem Bank. It ranks 4th of 15 18-month fixed rate bonds we track.

Rate checked Oct 2026Got this account? Leave a review

Fixed rate · 18 months

4.90%AER

Rate checked Oct 2026Got this account? Leave a review

Protection

FSCS£120,000

Min balance

£0

Max balance

No limit

Access

At maturity only

Interest paid

Anniversary

How It Stacks Up

Ranks 4th of 15

18-month fixed bonds we track

Above average

This account 4.90%

UK CPI (Aug 2026): 3.10%; Pays 1.80% more
Average 18-month fixed: 4.62%; Pays 0.28% more
Best 18-month fixed: 5.12%; Pays 0.22% less

Inflation: ONS. Averages and best rates: accounts on DepositScout.

Compare fixed bonds

Pros and cons

Pro: New and existing savers
Con: Your money is locked in for 18 months

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Estimated returns with Tandem Bank's Fixed Rate

What you could earn with Tandem Bank's 18 Month Fixed Saver.

Estimated interest

£1,000 saved

£74.39

At 4.9% AER

£5,000 saved

£372

At 4.9% AER

£10,000 saved

£744

At 4.9% AER

£50,000 saved

£3,720

At 4.9% AER

Estimated over the 18-month term, if the rate stays the same and interest is left in. Amounts outside the account's minimum or maximum aren't shown.

Work out the tax on your interestSee how much of this interest could be taxed.

Our Expert Opinion on Tandem Bank 18 Month Fixed Saver

Jan WatermannCo-Founder, DepositScout

Tandem Bank's 18 Month Fixed Saver pays 4.90%, which sits near the market average for fixed-rate savings and is 0.45% behind the current market leader at 5.35% across all terms. That said, 4.90% does beat August 2026 CPI of 3.1% by 1.80%, so your money grows in real terms. The main catch is the usual one for fixed bonds: no access until maturity, so only commit money you can genuinely leave untouched for 18 months. If you want a direct comparison, Chetwood Bank offers the same 4.90% rate on an equivalent 18-month fix.

Compare Fixed Rate Bonds