CUMIPMT in WPS Spreadsheet: Cumulative Interest by Payment Period
Calculate cumulative interest over explicit payment periods, reproduce a small amortization schedule and keep periodic rate, timing and cash-flow sign consistent.
Verification status: See the evidence and test scope described in this guide. How formula examples are checked
CUMIPMT returns the interest component paid over a selected interval of loan-payment periods. It does not return the entire payment, remaining balance or cumulative principal. With a positive borrowed principal, the lesson’s published example returns negative interest, expressing payments as cash outflows.
All amounts below are fictional mathematical controls. They illustrate a constant-rate repayment model, not a quote, borrowing recommendation or promise about fees and real loan terms.
Syntax and timing
=CUMIPMT(rate, nper, pv, start_period, end_period, type)
All six arguments are required. Rate is per payment period; nper is the total payment count; pv is the initial principal. Start and end identify the first and last included payment periods, numbered from 1. Type 0 means payments at period end; type 1 means payments at period beginning. Official WPS syntax and timing
The original calculations use explicit type 0. Beginning-period timing is documented, but it changes the schedule and is not interchangeable with the end-period controls.
Derive a two-payment example
Use rate 0.1 per period, two payments, principal 210, and end-period timing. The constant payment magnitude is 121, because:
210 = 121/1.1 + 121/1.1^2
The amortization arithmetic is then:
| Period | Opening principal | Interest | Payment magnitude | Closing principal |
|---|---|---|---|---|
| 1 | 210 | 21 | 121 | 110 |
| 2 | 110 | 11 | 121 | 0 |
Interest totals 21+11=32. Payments total 242, and 242−210=32 provides an independent cross-check. CUMIPMT’s expected cash-flow result is −32, not 242 and not −210.
Enter B2=0.1, B3=2 and B4=210. In B6 use:
=CUMIPMT(B2,B3,B4,1,2,0)
The result is a number in the same monetary unit as pv. No currency conversion is involved.
Select inclusive intervals
| Formula | Independent expectation |
|---|---|
=CUMIPMT(0.1,2,210,1,1,0) |
−21 |
=CUMIPMT(0.1,2,210,2,2,0) |
−11 |
=CUMIPMT(0.1,2,210,1,2,0) |
−32 |
=CUMIPMT(0.1,2,420,1,2,0) |
−64 |
The first two intervals each contain one payment. Their sum matches the full 1-through-2 interval. Doubling principal doubles the payment and both interest amounts when rate, term and timing stay fixed.
For an additional independent model, rate 0.2, principal 110 and two end-period payments produce payment 72: first interest 22 leaves principal 60; second interest 12 clears the balance. Thus =CUMIPMT(0.2,2,110,1,2,0) has expectation −34, with single-period values −22 and −12.
Practical case: reconcile an interest subtotal
A report that shows 32 as the positive magnitude of the expense may use the negative of the first full-range formula, provided its sign convention is stated. Keep the underlying cash-flow result −32 available for reconciliation. Taking an absolute value indiscriminately can hide a reversed-input or timing problem.
The period labels are payment indices, not automatically calendar months. A monthly schedule needs a monthly rate and a monthly payment count. Dividing a nominal annual rate by 12 is a model convention, not a universal conversion of every quoted effective annual rate. Ensure the input rate actually matches the repayment model.
Errors and boundaries
The lesson documents #NUM! for nonpositive rate, nper or pv; period indices below 1 or start greater than end; and timing types other than numeric 0 or 1. These are source statements, not executed error tests. The worked examples remain positive with integer intervals inside the two-payment term.
The page does not establish every coercion or out-of-term boundary. It also does not turn this constant-payment calculation into a model of variable rates, fees, extra repayments or irregular dates. Keep those changes explicit rather than forcing them into the same six inputs.
PMT concerns the whole periodic payment, and IPMT concerns a single interest component. SUM helps reconcile a separately calculated schedule.
Availability and evidence scope
The official WPS lesson is dated 2019-06-21 and explicitly applies to WPS Office for Windows Personal. Its numeric build is unspecified. This is a documented-by date, not a function introduction date; the first supported version and last functioning build remain unknown. The lesson does not establish Linux or other-edition parity, nor a retirement or deprecation history.
The complete text and vendor walkthrough were inspected on October 18, 2026. The original examples in this guide are documentation-derived and independently calculated, not executed in WPS or another spreadsheet engine. Vendor walkthrough observations are identified separately and are not native tests of these examples.