Available in version 0.9.0 and later.

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Overview

The effective_date feature is a critical functionality in financial systems that allows recording transactions with a financial date different from their system entry date. This capability ensures seamless migration, accurate financial reporting, reconciliation, and historical balance calculations.

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Effective date vs created date

When effective_date isn’t specified, the system automatically uses the created date as the effective date.
  • created_at: Timestamp of when the transaction was recorded in the system.
  • effective_date: The actual financial date when the transaction occurred

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Create transaction with effective date

Call the Record Transaction endpoint: 
POST http://YOUR_BLNK_INSTANCE_URL/transactions

{
  "amount": 358.90,
  "precision": 100,
  "reference": "unique_reference_1",
  "description": "Backdated transaction",
  "currency": "NGN",
  "source": "@source_account",
  "destination": "@destination_account",
  "effective_date": "2025-02-15T10:30:00Z"
}
Use the effective_date field (optional, string) to specify the date a transaction financially occurred, formatted in ISO 8601 (e.g., “2023-01-15T10:30:00Z”).If left blank, the system will automatically use the current timestamp.

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Balance calculations

In this section, you’ll learn how this affects how balances calculated.

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Current Running Balance

  • Backdated transactions immediately update the current running balance.
  • The running balance always reflects the most up-to-date financial position based on all known transactions.

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Example

  • Current balance before backdated transaction: $500.
  • Record a $200 transaction with an effective_date from last month.
  • Current balance after: $700.

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Historical Balance Queries

When querying a balance at a specific point in time, the system:
  1. Starts with the most recent snapshot before the requested time
  2. Applies all transactions with an effective_date on or before the requested time
  3. Ignores transactions with an effective_date after the requested time
Response example
{
  "balance_id": "bln_a03ef6af-1e5d-46a8-86a9-5fb1f2286f66",
  "balance": "1245.67",
  "credit_balance": "2000.00",
  "debit_balance": "754.33",
  "currency": "NGN",
  "timestamp": "2025-03-01T13:19:26Z"
}
In this example historical balance calculation includes:
  • All transactions with effective_date on or before March 1st, 2025.
  • Transactions recorded after March 1st are included if their effective date is on or before that date.

Historical balances

Learn how to use historical balances.

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Common use cases

Here are some use cases for backdating transactions:
  1. Late-arriving transactions: Record transactions that occurred in the past but were discovered later, ensuring historical accuracy with backdated entries.
  2. Month-end reconciliation: Attribute transactions to the correct fiscal period by backdating them, maintaining accurate financial records for period-end reporting.
  3. Financial reporting: Generate precise reports for specific time periods by backdating transactions to reflect their true financial occurrence, improving data integrity.
  4. Audit compliance: Maintain historically accurate records for auditing purposes by backdating transactions, ensuring compliance with regulatory requirements.
  5. Error correction: Rectify mistakes or omissions in past records by backdating transactions to their original dates, preserving ledger accuracy. See also: Adjusting Balances →.
  6. Historical analysis: Support retrospective financial analysis or trend tracking by backdating transactions, enabling accurate insights into past performance.

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Best practices & constraints

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Important Considerations

  • Backdated transactions immediately impact the running balance.
  • The effective_date:
    • Can be in the past.
    • Must not be in the future. Use scheduled_for instead to schedule transactions in the future. Learn how: Scheduling Transactions →.
    • Defaults to the current system time if not specified.

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Error Handling

Invalid effective date error: 
{
  "error": "Invalid effective_date: must not be in the future",
  "status": 400
}

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Need help?

We are very happy to help you make the most of Blnk, regardless of whether it is your first time or you are switching from another tool. To ask questions or discuss issues, please contact us or join our Discord community.