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Cash ISA Calculator

Use our cash ISA calculator to see what your ISA could be worth in the future.

3 Year Fixed Rate Cash ISA

from Hampshire Trust Bank

Interest Rate (AER) 1.16%
  • Term: 3 Years
  • Minimum Deposit £1
  • Interest paid annually
  • ISA transfers also allowed in
  • Maximum deposit £250,000
  • FSCS Protected
  • Winner of Platinum Feefo Trusted Service Award in 2021
  • Must be UK resident and be aged 18 or older
  • No withdrawals permitted

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

3 Year Fixed Rate Cash ISA

from Aldermore

Interest Rate (AER) 1.10%
  • Term: 3 Years
  • £1,000 minimum opening balance

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

2 Year Fixed Rate Cash ISA

from Hampshire Trust Bank

Interest Rate (AER) 1.06%
  • Term: 2 Years
  • Minimum Deposit £1
  • Interest paid annually
  • ISA transfers also allowed in
  • Maximum deposit £250,000
  • FSCS Protected
  • Winner of Platinum Feefo Trusted Service Award in 2021
  • Must be UK resident and be aged 18 or older
  • No withdrawals permitted

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

2 Year Fixed Rate Cash ISA

from Aldermore

Interest Rate (AER) 1.05%
  • Term: 2 Year

1 Year Fixed Rate Cash ISA

from Hampshire Trust Bank

Interest Rate (AER) 0.85%
  • Term: 1 Year
  • Minimum Deposit £1
  • Interest paid annually
  • ISA transfers also allowed in
  • Maximum deposit £250,000
  • FSCS Protected
  • Winner of Platinum Feefo Trusted Service Award in 2021
  • Must be UK resident and be aged 18 or older
  • No withdrawals permitted

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

1 Year Fixed Rate Cash ISA

from Aldermore

Interest Rate (AER) 0.85%
  • Term: 1 Year

30 Day Notice Cash ISA

from Aldermore

Interest Rate (AER) 0.55%
  • Term: Easy Access
  • Early withdrawals are permitted subject to loss of interest equivalent to the notice period
  • Open account with £1000

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

Online Easy Access Cash ISA

from Cynergy Bank

Interest Rate (AER) 0.50%
  • Term: Easy Access
  • Instant access to funds
  • Open account with £500

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

Easy Access Cash ISA

from Coventry Building Society

Interest Rate (AER) 0.30%
  • Term: Easy Access
  • Deposit from £1
  • Interest paid annually or monthly

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

Easy Access Cash ISA

from Shawbrook Bank

Interest Rate (AER) 0.30%
  • Term: Easy Access
  • Interest can be paid monthly or annually
  • ISA transfers in allowed
  • £250,000 maximum balance
  • FSCS Protected
  • Must be UK resident and aged 18 or older
  • No withdrawals permitted

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

Instant ISA Saver

from Nationwide

Interest Rate (AER) up to 0.05%
  • Term: Instant Access
  • Instant access
  • 0.01% interest on balances between £1 and £9,999, 0.03% on balances between £10,000 and £49,999, 0.05% on balances of £50,000 and above
  • Minimum deposit £1
  • Open and manage your account online or in branch
  • Covered by the FSCS (Financial Services Compensation Scheme)
  • Must be 16 or older
  • Must be UK resident

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

2 Year Fixed Rate Cash ISA

from Cynergy Bank

Interest Rate (AER) 0.80%
  • Term: 2 Years
  • Minimum deposit £500
  • Available to individual applicants aged 16 or over
  • Access to funds before the end of the term is subject to a fee equivalent to six months’ interest

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

3 Year Fixed Rate Cash ISA

from Shawbrook Bank

Interest Rate (AER) 0.87%
  • Term: 3 Years
  • Interest can be paid monthly or annually
  • ISA transfers in allowed
  • £250,000 maximum balance
  • FSCS Protected
  • Must be UK resident and aged 18 or older
  • No withdrawals permitted

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

1 Year Fixed Rate Cash ISA

from NatWest

Interest Rate (AER) 0.10%
  • Term: 1 Year
  • Instant access – manage your account by phone, in-branch and online
  • Open from £1000
  • Transfers allowed in – bring all your cash ISAs together in one place
  • Must be 16 or over
  • Must be a UK resident

1 Year Fixed Rate Cash ISA

from Royal Bank of Scotland

Interest Rate (AER) 0.10%
  • Term: 1 Year
  • Instant access – manage your account by phone, in-branch and online
  • Open from £1000
  • Transfers allowed in – bring all your cash ISAs together in one place
  • Must be 16 or over
  • Must be a UK resident

2 Year Fixed Rate Cash ISA

from Santander

Interest Rate (AER) Up to 0.20%
  • Term: 2 Years
  • Tax free ISA account
  • Open with £500 or transfer in existing ISA funds
  • 0.20% AER/tax-free for 2 years for savings of £500 and over if you're part of 1|2|3 World or Santander Select
  • FSCS Protected
  • 0.10% for balances of £40,000 or over, 0.01% for balances under £40,000
  • Must be UK resident
  • Must be aged 16 or older

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

2 Year Fixed Rate Cash ISA

from Royal Bank of Scotland

Interest Rate (AER) 0.10%
  • Term: 2 Year
  • Instant access – manage your account by phone, in-branch and online
  • Open from £1000
  • Transfers allowed in – bring all your cash ISAs together in one place
  • Must be 16 or over
  • Must be a UK resident

2 Year Fixed Rate Cash ISA

from NatWest

Interest Rate (AER) 0.10%
  • Term: 2 Year
  • Instant access – manage your account by phone, in-branch and online
  • Open from £1000
  • Transfers allowed in – bring all your cash ISAs together in one place
  • Must be 16 or over
  • Must be a UK resident

Easy ISA

from Santander

Interest Rate (AER) 0.01%
  • Term: Instant Access
  • Tax free ISA account
  • Open with £1 or transfer in existing ISA funds
  • Invest up to £20,000 per tax year
  • FSCS Protected
  • 0.10% for balances of £40,000 or over, 0.01% for balances under £40,000
  • Must be UK resident
  • Must be aged 16 or older

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

Instant Access Cash ISA

from NatWest

Interest Rate (AER) 0.01%
  • Term: Instant Access
  • Instant access – manage your account by phone, in-branch and online
  • Open from £1
  • Transfers allowed in – bring all your cash ISAs together in one place
  • Must be 16 or over
  • Must be a UK resident

Cash ISA Saver

from Lloyds Bank

Interest Rate (AER) 0.01%
  • Term: Instant Access
  • Tax free ISA account
  • Open with £1 or transfer in existing ISA funds
  • Invest up to £20,000 per tax year
  • Interest paid annually
  • FSCS Protected
  • Must be UK resident
  • Must be aged 16 or older

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

Instant Access Cash ISA

from Royal Bank of Scotland

Interest Rate (AER) 0.01%
  • Term: Instant Access
  • Instant Access
  • Open from £1
  • Online, phone or branch access
  • Transfers allowed in – bring all your cash ISAs together in one place
  • Must be a UK resident
  • Must be 16 or over

ISA Saver Variable

from Halifax

Interest Rate (AER) 0.05%
  • Term: Instant Access
  • Tax free ISA account
  • Open with £1 or transfer in existing ISA funds
  • Invest up to £20,000 per tax year
  • Interest paid annually
  • FSCS Protected
  • Must be UK resident
  • Must be aged 16 or older

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

Instant Cash ISA

from Barclays

Interest Rate (AER) 0.02%
  • Term: Easy Access
  • Deposit from £1
  • Interest paid annually

Calculate your interest with this plan

Your savings:
£
You could gain:
£0.00 (per tax year)

Cash ISA Calculator

Click here for ISA Calculator »

A cash Individual Savings Calculator is a program, mostly online, that helps you determine how much interest you could gain as interest on an ISA investment. While these tools only give a projection of the amount, they give valuable insight as to whether a certain interest rate is favorable and how much should be invested into the ISA regularly to give the best interest gains. A cash ISA calculator should not be used as the final determinant or decision maker when it comes to committing to a cash ISA. This is because it operates on assumptions to calculate a possible outcome on investment. That investment may gain more or less than estimated and is not an accurate measure.

Investment ISA Idea

Assumptions made on calculation

One of the assumptions made is that the individual will deposit money into the account on a regular basis. Cash ISAs give a lot of leeway when it comes to withdrawals and deposits. For that reason, it is not always necessary that an individual deposit money into the account on a regular basis in as long as the final tally on deposits does not exceed the cash ISA allowance limit.

Another assumption is that the market will be steady and the rates will be productive. Capital markets fluctuate all the time throughout the tax year. The market may grow or stunt considerably affecting the economical rates on conversion for the currency. Due to such changes therefore, the interest gained tends to fluctuate.

Another assumption made is that there shall be fixed tax rules throughout the duration of the tax year. The current tax allowance for ISAs exempts them from having to be taxed on interest made. However, the rules might change and in such a scenario, the tax rate could affect the projected figures.

It is also an assumption that there shall be no withdrawals made on the account. Most of the calculators work under the premise of compound interest. A withdrawal, which in reality will happen at one point or the other, has significant impact on interest.

Benefits of a cash ISA calculator

One of the benefits of using a cash ISA calculator is that it helps you predict your annual growth on a certain interest rate. From this prediction, you can then determine whether the interest rate offered is sufficient for your goals or whether you need to find a different rate elsewhere.

An ISA calculator also helps in determining how much money you should deposit on a regular basis, and at what time interval, to make it to the allowance limit, without having to compromise your financial situation.

Click here for ISA Calculator »

James Caldwell
Edited by James Caldwell - ISA.co.uk