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Debt Service Ratio: Calculate Payments and Remaining Cash
A payment ratio does not establish whether the remaining income can cover housing and food. Being below 30% does not guarantee safety. This educational definition uses take-home income; lenders may apply different definitions and local criteria.
Calculate with consistent assumptions
Add required installments for the same period, divide by net income and multiply by 100. Keep optional extra payments separate. With variable earnings, state the period used and test a lower-income month rather than relying on the best month.
An invented example in one currency unit
| Item | Monthly amount |
|---|---|
| Net income | 6000 |
| Three required payments | 900 + 600 + 300 = 1800 |
| Essential expenses | 3900 |
Ratio: 1800 ÷ 6000 × 100 = 30%. Remaining cash: 6000 − 1800 − 3900 = 300. If income drops to 5000, the ratio becomes 36% and the deficit is 700, with other expenses unchanged. This cash test is more informative than declaring a colored ratio band universally safe or dangerous.
What actually reduces the ratio?
An extra 300 payment reduces principal but may leave the required installment unchanged. If the third debt is formally closed and its 300 payment removed, required payments become 1500: 1500 ÷ 6000 × 100 = 25%. Wait for the creditor’s confirmation before recording that improvement. Extending a loan can lower the payment while increasing total costs. Compare fees, overall repayment and terms.
Monitor without promising a recovery date
- Verify balances, deadlines and fees from documents.
- Reserve essentials and required payments.
- If cash is short, ask for written options before a missed payment.
- Check income, balances and actual required payments monthly. A six-month return below a chosen threshold is not guaranteed.
