Glossary term
Mortgage stress test
A mortgage stress test is a qualification comparison that may use a higher qualifying rate than the mortgage contract rate.
Plain meaning
What the stress test means
The stress test is used to test whether a borrower could qualify under a higher rate assumption. It is not the same as the payment actually charged under the mortgage contract.
Formula role
How OpenBook uses it
Mortgage qualifier calculators use the stress-test rate as a qualifying-rate input. The calculator estimates a payment at that qualifying rate, then compares housing costs and debt payments with selected GDS and TDS limits.
The contract-rate payment and the stress-test qualifying payment can be different. Lenders may also apply additional rules, exceptions, or documentation requirements.
Common confusion
Qualification is not approval
A calculator result is a screening estimate. Mortgage approval can depend on lender policy, credit history, income documentation, property type, insurer rules, and other underwriting details.
Primary references
These links give the official mortgage-qualification context behind this term.