Skip to main content
Version: In-Progress

Loans and Amortization

Beancount (and this plugin) doesn't calculate amortization schedules for you — there's no built-in mortgage/loan calculator. What it's good at is recording the principal/interest split of each payment accurately, once you know what that split is, and keeping the running balance verifiably correct via reconciliation. This page covers that workflow.

Get the actual amortization schedule (the principal/interest split for each payment) from your lender's statement, loan documents, or an external amortization calculator/spreadsheet — that's your source of truth. The plugin's job is bookkeeping, not calculating it.

1. Open the loan account​

Open a Liabilities account for the loan, e.g. Liabilities:Loans:Car or Liabilities:Loans:Mortgage. See Adding Accounts and Commodities.

2. Record the disbursement​

When you take out the loan, record the money arriving and the liability being created in one transaction. For example, buying a car partly financed by a loan:

2026-01-15 * "Car dealership" "Financed vehicle purchase"
  Assets:Vehicles:Car          25000.00 USD
  Liabilities:Loans:Car       -22000.00 USD
  Assets:Checking              -3000.00 USD

Use + → Transaction tab to enter this — see Using the + Button.

3. Record each payment, split by principal and interest​

Every payment reduces the liability (principal) and records an expense (interest). A useful trick: fill in the two amounts you know for certain — the total payment leaving your checking account, and the interest amount from your statement — and leave the liability posting's amount blank. The plugin's auto-balance feature (see Postings) computes the exact principal portion for you:

2026-02-01 * "Car loan payment"
  Assets:Checking              -450.00 USD
  Expenses:Interest:CarLoan     180.00 USD
  Liabilities:Loans:Car

This is more reliable than typing the principal figure by hand, since it can't drift from a rounding mistake.

4. Set up a reminder (with a caveat)​

You can add this as a recurring schedule in the Upcoming Transactions tab (Monthly frequency) so you're reminded when a payment is due. Caveat: most loans have a slightly different interest/principal split every period as the balance amortizes, so treat the scheduled postings as a starting template — before you click Insert, edit the amount to match that period's actual interest figure from your statement, and leave the liability posting blank as above so it auto-balances correctly.

For an interest rate that never changes and a fixed payment, the drift period-to-period is usually small enough that reviewing before each insert takes seconds.

5. Reconcile against the lender's statement​

Periodically (monthly is typical), compare your ledger's Liabilities:Loans:Car balance against the payoff balance shown on your statement, and set a reconciliation interval on the account so the plugin reminds you to do this. See Periodic Reconciliation. If they drift apart, it usually means a payment was recorded with the wrong split, or a fee/escrow adjustment wasn't captured.

6. Reporting​

Tag loan-related transactions (e.g. #carloan) if you want to pull total interest paid over the life of the loan later:

SELECT sum(position) WHERE account ~ '^Expenses:Interest:CarLoan'

See Advanced Queries for more recipes like this.

7. Paying it off​

When the final payment brings the balance to exactly zero, you can close the account with a close directive (see Adding Accounts and Commodities) to keep it out of your active account list while preserving its history.