Simulation

How a Rate Change Affects Your Mortgage Payment

On a $300,000 30-year loan at 7%, a 1% rate rise lifts the payment from about $1,996 to roughly $2,235 — about $239 more a month and roughly $85,000 more in lifetime interest. A 1% drop saves the same. The effect is nearly linear near your current rate, so each quarter-point move is worth about $43 a month. This tool sweeps the rate so you can see the full range at once.

Results

Visualization

RateFig provides estimates for educational purposes only. Mortgage and loan figures depend on your credit, fees, points, and individual lender terms. This is not financial advice. Confirm every number with a qualified loan officer before making a decision.

How It Works

We recompute the fixed payment at the new rate using the loan formula and subtract the original payment to get the monthly change. Total interest at the new rate is payment × months − principal; the difference versus today is the lifetime cost of the move. The sweep steps the rate from -2% to +2% in quarter points and plots both the payment and total interest so you can read any scenario directly off the curve.

What Should You Do?

If you are shopping and rates rise before you lock, a float-down option or a short rate lock can protect you; if rates fall, a refinance may be worth it once savings exceed closing costs (see the breakeven tool). For an existing loan, a rate rise only matters at refinance or if you have an ARM. The monthly change is a good reality check on how much a delay in buying could cost or save you.

Frequently Asked Questions

Does the Fed set mortgage rates directly?

No. Mortgages track bond yields and expectations; Fed moves influence them but do not fix them.

How much is one quarter point?

On a typical loan, about $15-45 a month depending on size and term. Small but it adds up over 30 years.

Should I rush to lock if rates may rise?

A lock protects you, but weigh lock fees and float-down options. Base the decision on your timeline, not predictions.

Does this apply to my ARM?

Only at adjustment. For an ARM, the fixed-vs-ARM tool models the worst-case path instead.

Can rates go negative here?

The sweep clamps at zero; a negative rate is not modeled because it is not realistic for mortgages.

Is the payment change linear?

Nearly linear near your current rate, so you can roughly scale the per-quarter-point effect up or down.