Loan Payment Sensitivity to Rate

Excel Formulas › Analysis

All versionsPMT

How much does the monthly payment move if rates rise half a point? Lay rates across a row, compute PMT for each, and you have a sensitivity table that shows your exposure at a glance.


Quick formula: with a rate in each cell of a row, principal P and term N:
=PMT(rate/12, N, -P)
Fill the formula across the rate row. Each cell shows the payment at that rate — an instant sensitivity strip.

Functions used (tap for the full reference guide):

The example

Payment on $25,000 / 60 months across rates.

ABC
1Rate5.5%6.0%
2Payment$477.53$483.32

The formula

One PMT per rate:

=PMT(B1/12, 60, -25000) // copy across the rate row

How it works

A simple formula row beats a Data Table here:

  1. Put the rates across a row (5.0%, 5.5%, 6.0%…).
  2. Below each, compute =PMT(rate/12, term, -principal), locking principal and term with $.
  3. Copy across — the payment recalculates for each rate.
  4. Add a row for total interest (payment × term − principal) to see the full cost impact, not just the payment.

Show the delta: a row of =thisPayment − basePayment highlights how many dollars each rate step adds — the number that actually matters for budgeting against a rate rise.

Try it: interactive demo

Live demo

Payment vs rate ($, term below).

Variations

Total interest row

Full cost impact:

=PMT(r/12,N,-P)*N - P

Delta vs base

Dollars per rate step:

=thisPayment - basePayment

As a 2-way grid

Add term variation → data table.

Pitfalls & errors

Lock principal & term. Use $ so only the rate varies as you copy across.

Annual vs monthly. Divide the annual rate by 12 and use months for the term, consistently.

Sign of principal. Enter it negative (or negate PMT) for a positive payment.

Practice workbook

📊
Download the free Loan Payment Sensitivity to Rate practice workbook
A payment-vs-rate sensitivity strip with total-interest and delta rows, plus 4 challenges with answers. No sign-up required.

Frequently asked questions

How do I see how a loan payment changes with the rate?
Lay rates across a row and compute =PMT(rate/12, term, -principal) under each, locking principal and term. Each cell shows the payment at that rate.
How do I show the total interest impact too?
Add a row: =PMT(rate/12, term, -principal)*term - principal gives total interest at each rate.
How do I vary rate and term together?
Use a two-variable data table with rate down one axis and term across the other.

Stop fighting formulas. Learn them in a day.

This recipe is one of hundreds of real-world formulas we teach. Our Excel Formulas & Functions class covers lookups, logic, text, and dynamic arrays hands-on — live in Dallas–Fort Worth, Houston, Austin, Oklahoma City, Denver, or online.

See the Formulas & Functions Class

Related formulas: One-variable data table · Loan comparison · Calculate a loan payment

Function references: PMT