Apple Numbers IPMT: Interest Portions, Payment Timing and Balloon Loans

• Introduced: The original introduction release and date are not established by the checked sources.
• Availability: Currently documented in Apple’s Functions Help 15.4 documentation edition; no final supported-version endpoint is established.
• Scope: Shared iWork reference. Exact historical availability in individual Mac, iPad, iPhone and iCloud builds remains unverified.
• Checked: October 14, 2026, against the official IPMT reference. Documentation and independent payment schedules; no native Numbers test.

=IPMT(periodic-rate, period, num-periods, present-value, future-value, when-due)

The first four arguments are required: rate per payment period, payment number, total number of periods and initial value. Period must be greater than zero; Apple’s entry lists num-periods as at least zero. The examples use positive whole-number terms and payment numbers within the term, avoiding degenerate or out-of-range cases whose outcomes are not fully specified.

Future-value is optional and defaults to 0. When-due is optional: 0 or omitted means end-of-period payments; 1 means beginning-of-period payments. The rate and period count must use the same time unit. Use 6%/12 for a nominal annual rate of 6% with monthly periods, rather than entering 6% as the monthly rate.

A loan received initially is a positive present value; repayments are negative cash flows. A remaining balloon liability is entered as a negative future value. Currency formatting follows regional settings but does not change these signs or the timing model.

Create a Numbers table named InterestParts, with seven columns A:G and four rows including one header row. Put Period, Interest, Principal, Total payment, Parts check, Opening balance and Closing balance in A1:G1. Enter 1, 2, 3 in A2:A4.

Enter these formulas in row 2 and fill B2:E2 through row 4:

• B2: =IPMT(10%,A2,3,331,0,0)
• C2: =PPMT(10%,A2,3,331,0,0)
• D2: =PMT(10%,3,331,0,0)
• E2: =B2+C2

Put 331 in F2 and =F2+C2 in G2. Put =G2 in F3 and =F3+C3 in G3, then fill F3:G3 through row 4.

The independent interest check is negative opening balance × 10%. The total payment stays constant while its interest portion falls and principal portion grows. Adding the negative principal amount to the positive opening balance gives the closing loan balance.

Keep InterestParts intact. Create another table named BeginningPayments, with four columns A:D and four rows. Enter 1, 2, 3 in A2:A4. Use Interest, Principal and Payment as B1:D1.

Enter =IPMT(10%,A2,3,331,0,1) in B2, =PPMT(10%,A2,3,331,0,1) in C2 and =PMT(10%,3,331,0,1) in D2. Fill B2:D2 through row 4.

The independent interest targets are 0, -21, -11; principal targets are -121, -100, -110. Each total payment is -121. The first payment occurs immediately, before a period of interest accrues. After it, 210 remains; its next period’s interest is 21. After the second principal reduction, 110 remains and the following interest is 11.

Changing when-due changes the full payment schedule, not just the label on the first row. These are model-derived checks; keep the original end-payment table for comparison.

Create a separate table named BalloonCheck, with two columns and five rows. Use A for labels and enter the following formulas in B2:B4:

• B2: =IPMT(6%/12,25,120,200000,-100000,0) → approximately -922.406466292
• B3: =PPMT(6%/12,25,120,200000,-100000,0) → approximately -687.798553125
• B4: =PMT(6%/12,120,200000,-100000,0) → approximately -1610.205019416

Put =B2+B3 in B5; its mathematical target matches B4. Apple’s two-decimal results are -922.41, -687.80 and -1610.21. The higher-precision values above are independent model calculations, not claims about native stored bits.

Payment 25 is the first monthly payment of year three. The -100000 future value represents the balance still owed after the regular payments; it is not an additional receipt. If you omit future-value, you select a zero-ending-balance model instead.

IPMT is based on fixed rates and fixed periodic payments. It does not infer fees, irregular payment dates, extra repayments or changing rates from adjacent cells. Apple permits negative rates in the entry but cautions that interpretation can be difficult; the worked models here use positive rates.

The page does not enumerate every exact native error, fractional-period rule or zero-term outcome. Keep calculations at stored precision and round only for presentation unless a separate posting policy explicitly rounds each installment.

PPMT returns principal and PMT returns their total. CUMIPMT aggregates interest across a specified interval; it has its own stricter argument rules and no future-value argument.