The amount you can borrow for a mortgage based on your income depends on several factors, including your income level, debt obligations, credit history, and the specific lending criteria of the financial institution you approach. In general, lenders use the above income-percent guidelines to determine the mortgage amount you may qualify for. The Gross Debt Service (GDS) ratio assesses the proportion of your gross income that can be allocated toward housing costs (including mortgage payments, property taxes, and heating expenses). The GDS ratio typically should not exceed 35-45% of your gross income, although this can vary depending on the lender and other factors. Another important factor lenders consider is the Total Debt Service (TDS) ratio, which considers your total monthly debt payments (including housing costs) in relation to your gross income. The TDS ratio generally should not exceed 42-50% % of your gross income, but this can vary based on lender requirements.