Mortgage refinancing can save tens of thousands over the life of a loan — or cost more than it saves. The decision depends on rate spread, closing costs, how long you'll stay in the home, and tax considerations. Here is the math.
When refinancing makes sense
Conventional wisdom: refinance when rates drop 1%+. Modern reality: refinance when MONTHLY SAVINGS exceed CLOSING COSTS within your time horizon.
| Rate spread (current to new) | Rough recommendation |
|---|---|
| Less than 0.5% | Usually not worth closing costs |
| 0.5% to 0.75% | Worth it IF closing costs < 12 months of savings |
| 0.75% to 1.5% | Usually worth it if staying 3+ years |
| 1.5%+ | Almost always worth it |
The break-even calculation
Break-even months = Closing costs ÷ Monthly savings
Example: $300K mortgage at 7.5% (existing) → 6.0% (new). 30-year fixed.
- Old payment: $2,098/mo P&I
- New payment: $1,799/mo P&I
- Monthly savings: $299
- Closing costs: $5,000-$8,000 (typical)
- Break-even: 17-27 months
If you'll stay in the home longer than 27 months, refi pays off. Sell sooner and you lose money on the refi.
Closing costs to expect
- Origination fee: 0.5-1% of loan amount
- Appraisal: $400-$700
- Title insurance: $500-$2,000
- Title search: $200-$400
- Recording fees: $100-$250
- Underwriting: $300-$900
- Discount points (optional): 1% of loan = approximately 0.25% rate reduction
- Escrow setup: 2-3 months of property taxes + insurance
Total typically 2-5% of loan amount. Some lenders offer "no closing cost" refinances by rolling costs into a higher rate or higher loan balance — usually worse over the long term.
Cash-out refinance considerations
Cash-out refi lets you borrow against home equity by replacing existing mortgage with a larger one. Use cases:
- Debt consolidation: if mortgage rate is much lower than credit card APR (which it usually is — 7% vs 22%)
- Home improvements: tax-deductible if for substantial improvements
- Investment: only if expected return clearly exceeds new mortgage rate
Avoid cash-out refi for: vacations, cars (different financing better suited), or anything that doesn't produce return higher than the mortgage rate.
Rate-and-term vs cash-out refi differences
| Rate-and-term | Cash-out | |
|---|---|---|
| Purpose | Lower rate or change term | Borrow additional money |
| Rate impact | Often lower than purchase rate | Often 0.25-0.5% higher than rate-and-term |
| Max LTV | Usually 95%+ | Typically 80% |
| Tax deduction | Same as original mortgage | Only if used for substantial home improvement |
When NOT to refinance
- Selling within 2 years
- Recently extended your term (refinancing back to 30 years means more total interest)
- Closing costs would take longer than time horizon to recover
- Rate spread is less than 0.5% (savings often don't justify hassle)
- You'd give up favorable terms (assumable mortgage, no PMI when refi would require PMI)
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Browse all →Frequently Asked Questions
- What's the lowest rate spread that makes refinancing worthwhile?
- Roughly 0.75% with normal closing costs and 3+ year time horizon. Lower spreads can work if you have very low closing costs or plan to stay 5+ years.
- Should I shorten my term when refinancing?
- Often yes — refinancing from 30-year to 15-year while rates are favorable saves enormous total interest. But monthly payment is higher.
- How long does refinancing take?
- Typically 30-45 days from application to closing. Cash-out and complex situations may take 60-90 days.
- Will refinancing hurt my credit?
- Temporary 5-10 point dip from the hard inquiry. Recovers within 6 months. Long-term, the lower payment can help if it improves your debt-to-income ratio.
- Can I refinance with bad credit?
- Yes but at much higher rates. Conventional refi typically requires 620+ credit; FHA refi works down to 580. If credit is recovering, sometimes worth waiting 6-12 months for better rate.
Educational only — not legal, financial, or tax advice. Tax law and rates change. Consult a CPA or financial advisor for your specific situation.