Skip to content
ENExplore Calculators

Buy Now Pay Later Cost Calculator

Work out buy now pay later cost instantly with clear inputs, formula shown and shareable results.

About Buy Now Pay Later Cost Calculator

Buy-now-pay-later splits a purchase into equal instalments with no interest if paid on time. The cost sits entirely in late fees, which annualise into a high effective rate because the borrowing period is only a few weeks.

Formula

BNPL cost

Instalment = purchase / k; Effective APR = fees/purchase × 52/weeks × 100

Worked example

With the default values below, Buy Now Pay Later Cost Calculator returns Total Cost Including Fees of $25,500.00. Change any input above and every figure here is recalculated in your browser.

Inputs used

Purchase Amountminimum 0
25,000
Number Of Instalmentsaccepts 2–24
4
Late Fee Per Missed Paymentminimum 0
500
Instalments Expected To Be Missedaccepts 0–24
1

Results

Total Cost Including Fees
$25,500.00
Amount Per Instalment
$6,250.00
Late Fees
$500.00
Effective Annualised Cost Of Fees
13.00%

Step by step

  1. 1Values used
  2. 2BNPL cost
  3. 3Total Cost Including Fees= 25,500.00
  4. 4Amount Per Instalment= 6,250.00
  5. 5Late Fees= 500.00
  6. 6Effective Annualised Cost Of Fees= 13.00

Assumptions and limits

  • The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
  • In particular, this calculator does not take inflation, tax or compounding frequency into account.
  • Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
  • Figures are estimates. Lenders apply their own rounding, fees and eligibility rules, and rates change. This is not financial advice — confirm the numbers with your lender.
  • This is an estimate for general information and not professional financial, tax or legal advice. See the full disclaimer for the limits that apply to this kind of calculator.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Figures are estimates. Lenders apply their own rounding, fees and eligibility rules, and rates change. This is not financial advice — confirm the numbers with your lender.

Frequently Asked Questions

Is BNPL really interest-free?

Only if every instalment lands on time. One missed payment can cost more than a month of card interest on the same amount.

Does BNPL appear on a credit file?

Increasingly yes, and missed instalments can be reported like any other default.

Related Calculators

Buy Now Pay Later Cost Calculator | Calcrivo