Avalanche vs. snowball for student loans
If you have multiple loans, avalanche (highest rate first) saves the most money. Snowball (smallest balance first) builds momentum but costs more in interest. For 2026 borrowers with mixed federal + private, the avalanche almost always means killing private loans first (often 8–13% APR), then grad PLUS (8.05%), then undergrad federal (6.5%) last.
When NOT to pay extra on student loans
Skip extra payments if: (1) you're not capturing full 401(k) match — that's a 100% return; (2) you have credit card debt at 18%+ APR; (3) you have <3 months emergency fund; (4) you're on track for PSLF/IDR forgiveness (extras reduce the forgiven amount); (5) you have a low loan rate (<5%) and high-conviction better investments.
The biweekly payment trick
Splitting your monthly payment in half and paying every 2 weeks results in 26 half-payments = 13 full payments per year, vs. 12 if paid monthly. The extra payment is applied automatically to principal. For a $40K loan at 6.5%, this cuts about 1.5 years off the term with zero behavior change.
Lump sums: tax refund, bonus, inheritance
Putting a $5,000 tax refund toward a $40K student loan at 6.5% saves $1,200+ in interest and shortens the term by 8 months. Confirm with your loan servicer that extra is applied to principal, not 'paid ahead' on future installments (a common loan servicer trick that doesn't actually shorten the term).
Related guides
Long-form playbooks on the same topic, written by the RevenueLab editorial team.
FAQ
Will extra payments actually shorten my loan?
Yes, IF applied to principal. Confirm with your servicer in writing — some servicers apply 'extra' as 'paid ahead' on the next monthly bill, which doesn't shorten the term or save interest. Specify 'apply to principal' on every extra payment.
Should I pay extra or invest the difference?
Above ~6% loan rate, paying extra is mathematically better than investing (guaranteed return). Below 5%, investing in a Roth IRA at expected 7–10% market return usually wins. Between 5–6% is a judgment call about risk tolerance.
Is student loan interest still tax-deductible?
Yes, up to $2,500/year, phasing out between $80K–$95K income (single) or $165K–$195K (joint) for 2026. The deduction reduces the effective cost of the loan by ~22% for most borrowers.
What's the best payoff strategy for $200K+ in loans?
For high-income earners (physicians, lawyers): aggressive payoff over 5–7 years usually wins. For PSLF-eligible (residents, nonprofit attorneys): minimum IDR payments + PSLF forgiveness. Run both scenarios — the breakeven income is around $200K.
Can I pay off federal loans early without penalty?
Yes. All federal student loans have zero prepayment penalty. Most private student loans also lack prepayment penalties, but confirm in your promissory note.
Should I refinance before or after extra payments?
If you're going to refinance, do it first — extra payments on a 6.8% federal loan reduce your refi-eligible balance, so the savings compound. If you're not refinancing, just attack the highest-rate balance.
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Written by Sam Doshi and the RevenueLab editorial team. We don't sell the data feeds this tool is built on.
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Last reviewed
June 2026. We re-check every figure on the platform on a rolling quarterly cycle.
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See our editorial policy and disclaimer. Results are estimates, not advice.