Interest configuration

Interest configuration

Using the interest configuration endpoints, you can update the interest configuration of your existing savings accounts. This functionality is enabled on a per-client basis. If you're interested in using this functionality, please speak to your Client Director.

The initial interestConfigurationId is usually set during account creation. You can request a new configuration ID from your usual ClearBank contact.

You can:

• Update your interest configuration using the POST /interest/v1/accounts/{accountId}/configurations endpoint
• Get all interest configurations set for an account using the GET /interest/v1/accounts/{accountId}/configurations endpoint
• Set future-dated interest configurations using the PUT /v1/accounts/{accountId}/future-configurations endpoint
• Delete all future interest configurations using the DELETE /v1/accounts/{accountId}/future-configurations endpoint

The interest rate will apply for the whole of the day on which it is set. Interest is calculated in the early hours of the following morning based on data from midnight UK time.

Daily interest example

If you update an interest product at 15:00 on Tuesday, all of Tuesday's interest, even before 15:00, will be calculated at the new interest rate. The Interest Paid and Transaction Settled webhooks will notify you of the amount of interest paid each day.

This diagram shows the message flow:

Monthly interest example

If you update an interest product at 14:00 on the 5th, interest from the 1st to the 4th will be calculated at the previous rate at the end of the month. Interest from the 5th until the end of the month will be calculated using the new rate. The Interest Paid and Transaction Settled webhooks will notify you of the amount of interest paid at the end of the month.

This diagram shows the message flow:

Future-dating interest configurations

You can set multiple future interest configurations for your account with the PUT /v1/accounts/{accountId}/future-configurations endpoint.

Each selected interest configuration will apply from the start of the day provided in the effectiveFrom field. For example, you might set an account to move from interest config A to interest config B on 1 August. Interest will be calculated based on the balance from midnight on 31 July using interest config A. Any future interest interest calculations will be based on interest config B until any further changes to the interest configurations come into effect.

If you update the interest configuration using the POST /interest/v1/accounts/{accountId}/configurations endpoint while future-dated configurations are set, the update will remain active until the next future-dated configuration takes effect. For example, updating to config C on 1 October will apply until 14 October if a future-dated config D is set to start on 15 October. Config D will then take effect as scheduled.

Use the DELETE /v1/accounts/{accountId}/future-configurations endpoint to remove all future-dated interest configurations from an account. The account will remain on its current interest configuration.

This diagram shows an example scenario where you have an introductory interest rate and daily interest payments:

For monthly interest payments, it works similarly: if you future-date an interest product to change on 10 November, interest from 1 to 9 November will be calculated at the initial rate. Interest from 10 November until the end of the month will be calculated using the new rate. The Interest Paid and Transaction Settled webhooks will notify you of the amount of interest paid at the end of the month.

Multiple interest configurations example

Multiple interest configurations allow you to offer different interest rates based on the type of product or membership a customer has. Customers can seamlessly switch between products without closing and reopening their account.

In this example, three different savings account memberships are available:

1. Standard Membership (Product A): This is a non-paid membership where customers earn a 2% interest rate on their savings.
2. Silver Membership (Product B): For a £5 monthly fee, customers earn a 5% interest rate on their savings.
3. Gold Membership (Product C): For a £10 monthly fee, customers earn an 8% interest rate on their savings.

• If a customer with a Standard Membership decides to upgrade to a Silver Membership, they would start earning a 5% interest rate instead of 2%.
• If a customer with a Gold Membership decides to downgrade to a Standard Membership, they would start earning a 2% interest rate instead of 8%.

Interest tiers

You can configure multiple interest tiers when agreeing an interest configuration with us. Tiers allow you to specify balance ranges, each with its own interest rate, allowing you to offer different levels of interest depending on account balance. There are two methods for applying interest to tiers:

• Whole - The total balance of the account earns the rate of the tier it falls into.
• Segregated - Each part of the account balance earns the rate for its range.

Interest tiers example:

Using the tier examples above, an account with a balance of £7,500.00 would earn interest in the following way depending on the method applied:

• Whole: The total balance is in the range of tier 3, so an interest rate of 4.75% applies to the whole balance
• Segregated:
  • The first £1,000.00 falls into tier 1 and earns an interest rate of 3.00%
  • The next £4,000.00 falls into tier 2 and earns an interest rate of 4.00%
  • The remaining £2,500.00 falls into tier 3 and earns an interest rate of 4.75%

{
  "future": [
    {
      "effectiveFrom": "2025-08-24",
      "interestConfigurationId": "24df1e52-24d9-4bda-86af-c81a7d1932b1",
      "name": "string"
    }
  ],
  "current": {
    "effectiveFrom": "2025-08-24",
    "interestConfigurationId": "24df1e52-24d9-4bda-86af-c81a7d1932b1",
    "name": "string"
  },
  "past": [
    {
      "effectiveFrom": "2025-08-24",
      "interestConfigurationId": "24df1e52-24d9-4bda-86af-c81a7d1932b1",
      "name": "string"
    }
  ]
}

{
  "type": "string",
  "title": "string",
  "status": 0,
  "detail": "string",
  "instance": "string",
  "property1": null,
  "property2": null
}

{
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{
  "interestConfigurations": [
    {
      "id": "a7a907c5-7062-4d76-8e6c-3b203a758839",
      "payablePeriod": "Daily",
      "payableAccountId": "7e5e3b83-d76e-4821-9566-a83b322ce2dd",
      "effectiveFrom": "2025-08-15",
      "effectiveTo": "2025-09-15",
      "timeStampCreated": "2025-08-18T11:11:45.5666667",
      "timeStampModified": "2025-09-18T09:00:45.5666667",
      "payablePeriodOffset": 0,
      "interestPaymentRoundingAlgorithm": "Truncate",
      "doUnpaidAccrualFractionsRollover": "false",
      "tierBalanceAllocation": "Whole",
      "interestRate": 7,
      "tiers": [
        {
          "id": "99b386f8-c2f7-4fda-b946-c1384b44bb84",
          "fromAmount": 0,
          "toAmount": 1000,
          "percentPayable": 0.5,
          "clearbankMargin": 0.2,
          "grossRate": 6.3,
          "aer": 6.50210494
        }
      ]
    }
  ]
}

{
  "type": "string",
  "title": "string",
  "status": 0,
  "detail": "string",
  "instance": "string",
  "property1": null,
  "property2": null
}

{
  "interestConfigurationId": "5C35D48D-0R3D-47BE-9F54-I9F3328L7V2A"
}

{
  "accountId": "3d07c219-0a88-45be-9cfc-91e9d095a1e9",
  "interestConfigurationId": "24df1e52-24d9-4bda-86af-c81a7d1932b1",
  "effectiveFrom": "2025-08-24"
}

{
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  "title": "string",
  "status": 0,
  "detail": "string",
  "instance": "string",
  "property1": null,
  "property2": null
}

{
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}

{
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}

{
  "interestConfigurations": [
    {
      "interestConfigurationId": "24df1e52-24d9-4bda-86af-c81a7d1932b1",
      "effectiveFrom": "2027-10-01"
    }
  ]
}

{
  "type": "string",
  "title": "string",
  "status": 0,
  "detail": "string",
  "instance": "string",
  "property1": null,
  "property2": null
}

{
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  "title": "string",
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  "detail": "string",
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  "property1": null,
  "property2": null
}

{
  "type": "string",
  "title": "string",
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  "detail": "string",
  "instance": "string",
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}

{
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}