Overview

As part of Lithic's changes to Loan Tape Tier Schedules, we are also unlocking the ability for customers to retroactively change interest rates.

Customers can use this functionality to handle interest rate changes that are impacted by Military Lending Act (MLA) and Servicemembers Civil Relief Act (SCRA).

Please note that this endpoint has usage limits to maintain optimal performance. If you anticipate high-volume needs for retroactively calculating interest, please contact Lithic Implementations to discuss your use case.

Details

To retroactively update interest calculations for a financial_account, customers should call the Update Interest Tier Schedule Endpoint

Path Parameters

Parameter	Type	Required	Description
`financial_account_token`	string (uuid)	Yes	The unique identifier for the financial account
`effective_date`	string	Yes	The date of the tier schedule (YYYY-MM-DD format)

Request Body

{
  "credit_product_token": "test_token",
  "tier_rates": {
    "purchase": {
      "rate": "0.06",
      "cap_rate": "0.06"
    },
    "cash_advance": {
      "rate": "0.06",
      "cap_rate": "0.06"
    },
    "balance_transfer": {
      "rate": "0.06",
      "cap_rate": "0.06"
    }
  }
}

Success Response (200 OK)

{
  "effective_date": "2025-12-15",
  "credit_product_token": "test_token",
  "tier_rates": {
    "purchase": {
      "rate": "0.06",
      "cap_rate": "0.06"
    },
    "cash_advance": {
      "rate": "0.06",
      "cap_rate": "0.06"
    },
    "balance_transfer": {
      "rate": "0.06",
      "cap_rate": "0.06"
    }
  },
  "created_at": "2024-01-10T14:30:00Z",
  "updated_at": "2026-01-29T14:30:00Z"
}

When the effective_date in the path is in the past, a successful response will trigger a rebuild of the loan tapes on the next day. You can see this by calling Get Loan Tape Configuration and seeing requires_rebuild set to true. The next day, customers will receive the loan tape webhook for each day that requires rebuild.

{
  "instance_token": "7c9e6679-7425-40de-944b-e07fc1f90ae7",
  "financial_account_token": "8d8e7890-8536-51ef-055c-f18gd2g01bf8",
  "credit_product_token": "test_token",
  "loan_tape_rebuild_config": {
    "requires_rebuild": true,
    "rebuild_from": "2025-12-15",
    "last_rebuild": "2024-01-15"
  },
  "tier_schedule_changed_at": "2026-01-29T14:30:00Z",
  "created_at": "2024-01-10T14T14:30:00Z",
  "updated_at": "2026-01-29T14:30:00Z"
}

Release Timeline

Available now: February 24, 2026.

User Impact

This change is additive only. Customers whose Credit Product was created before February 24, 2026, will need to have their credit_product migrated to use this functionality. Reach out to Lithic implementations and we will facilitate your migration.

Learn more about Statements and Loan Tape APIs via our API Reference

If you have any questions or concerns, please contact us via the HELP link in your Lithic Dashboard.

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