Cash ISACompare 3 Year Fixed Rate Cash ISAs

Monmouthshire Building Society 3 Year Fixed Rate Cash ISA Review

A three-year cash ISA from Monmouthshire Building Society, with a £1,000 minimum deposit. It ranks 27th of 35 three-year cash ISAs we track.

Fixed rate · 3 years

4.40%AER

Rate checked Oct 2026Got this account? Leave a review

Protection

FSCS£120,000

Min balance

£1,000

Max balance

£20,000

Access

3 Years

Interest paid

Annually/On maturity

Transfers in

Accepted

How It Stacks Up

Ranks 27th of 35

3-year cash ISAs we track

Below average
This account 4.40%
UK CPI (Aug 2026)
3.10%
Pays 1.30% more
Average 3-year cash ISA
4.66%
Pays 0.26% less
Best 3-year cash ISA
5.15%
Pays 0.75% less

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

Compare cash ISAs

A Good Fit For

  • Pro: New and existing savers
  • Pro: Flexible: take money out and put it back in the same tax year without using more allowance

Worth Weighing Up

  • Con: You need at least £1,000 to open it

Please verify all details with the provider – see our Disclaimer

See all Monmouthshire Building Society accounts

Estimated returns with Monmouthshire Building Society's Cash ISA

What you could earn with Monmouthshire Building Society's 3 Year Fixed Rate Cash ISA.

Estimated interest

£1,000 saved

£138

At 4.4% AER

£5,000 saved

£689

At 4.4% AER

£10,000 saved

£1,379

At 4.4% AER

£20,000 saved

£2,758

At 4.4% AER

Estimated over the 36-month term, if the rate stays the same and interest is left in. Amounts outside the account's minimum or maximum aren't shown.

Our Expert Opinion on Monmouthshire Building Society 3 Year Fixed Rate Cash ISA

Jan WatermannCo-Founder, DepositScout

This account suits someone who wants to lock ISA savings away for three years and is comfortable with Monmouthshire Building Society as their provider. The rate is 4.40%, which sits below the market average for cash ISAs and is 0.85% behind the category leader at 5.25%, so it is hard to call this competitive. At 1.30% above August 2026 CPI of 3.1% your money does at least beat inflation in real terms. The real catch beyond the lock-in itself is the early exit penalty: closing or transferring out costs 270 days of interest on the closing balance, and the maximum deposit is capped at £20,000.

Compare Cash ISAs

2 alternatives to Monmouthshire Building Society's 3 Year Fixed Rate Cash ISA

Same type of account, closest on rate.

Common questions about the 3 Year Fixed Rate Cash ISA

D

DepositScout Alerts

Example alert

Easy Access rate just dropped

A top provider just cut their rate. Here's what you need to know about the latest market shift.

Example Easy Access Saver Rate Down
4.20% AER
4.75%
View Best Rates
Live Market Tracking

Be the first to know when this Monmouthshire Building Society rate drops.

Join 1,000+ savers using DepositScout who get instant email alerts when top UK savings rates change. Never miss out on a better deal again.

Takes 30 seconds · No spam · Unsubscribe any time