Rule 1: Don’t Borrow More Than Your Expected First-Year Salary
Verdict: Still valid — possibly the most important rule. Borrowers who exceed 1.5× first-year salary at graduation consistently experience repayment hardship. The standard 10-year plan payment on 1.5× salary debt exceeds 10% of monthly gross income — the threshold for payment stress.
Rule 2: Keep Monthly Payment Under 10% of Gross Income
Verdict: Valid as a comfort guideline. At 10% of gross, the payment is demanding but manageable. Above 15%: financial stress is likely. Above 20%: income-driven repayment is probably necessary. Calculate this before borrowing: loan amount × 1.0% (rough monthly payment estimate) ÷ expected monthly gross.
Rule 3: Refinance When Your Rate Is Above 5%
Verdict: Too simple for federal loans. Refinancing federal to private above 5% ignores the value of PSLF, income-driven forgiveness, and federal hardship protections. This rule applies to private loans (where there are no forgiveness options). For federal loans: only refinance if you’ve explicitly eliminated PSLF eligibility and are confident in income stability.
2025 status of major student loan rules of thumb
| Rule | 2025 Verdict | When to Deviate |
|---|---|---|
| Borrow ≤ 1× first-year salary | Valid | Only for very high-ROI degrees with exceptional job placement |
| Payment ≤ 10% of gross | Valid guideline | IDR available when above 10% for federal loans |
| Refinance above 5% federal | Too simplistic | Never refinance federal without full PSLF analysis first |
| Always use standard repayment | Outdated for high DTI | IDR wins mathematically when DTI > 1.0× |
| Pay extra whenever possible | Valid if not PSLF-eligible | Never pay extra if pursuing PSLF — let forgiveness work |
Test the Rules Against Your Situation
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