Glossary term
GDS ratio
GDS ratio, or gross debt service ratio, compares selected housing costs with gross household income.
Plain meaning
What GDS ratio means
GDS ratio is a mortgage qualification measure. It focuses on housing costs, such as mortgage payment, property taxes, heating, and applicable condo or site costs, compared with gross income.
Formula role
How OpenBook uses it
Mortgage qualifier calculators estimate housing costs under the stated mortgage assumptions and compare that amount with gross household income. The result is then compared with the selected GDS limit.
The GDS calculation is often paired with TDS ratio, which includes other debt obligations.
Common boundary
A screening ratio, not approval
GDS is one qualification screen. Lenders and insurers can apply additional requirements, documentation rules, credit criteria, and product-specific treatment.
Primary references