Cash-out refinance breakeven

Cash-out refinance breakeven — when the math works (and when it doesn't)

A cash-out refinance can be a powerful financial tool or an expensive mistake depending on rate, term, intended use of funds, and how long you stay in the home. The monthly payment comparison alone is misleading — the only honest analysis looks at total interest over the life of both loans.

Cash-out refi vs. HELOC vs. home equity loan

Cash-out refinance: Replaces your entire mortgage with a new first mortgage. Typically the lowest rate but highest closing costs ($3,000–$8,000+). Resets your loan term to 30 years. Best when you also want to lower your rate or remove PMI.

HELOC (Home Equity Line of Credit): A revolving second mortgage. Variable rate tied to prime. Interest-only payments in the draw period (typically 10 years). Lower closing costs. Best for ongoing needs (renovations, irregular expenses). Risk: variable rates that can spike.

Home Equity Loan (HEL): A fixed-rate second mortgage paid as a lump sum. Predictable payments. Lower closing costs than a refi. Does not touch your existing mortgage or rate. Best when your first mortgage has a favorable rate you want to preserve.

The term reset trap

The most underappreciated cost of a cash-out refi is resetting to a new 30-year term. If you're 5 years into a 30-year mortgage and refinance, you replace 25 remaining years with 30 new years — adding 5 years of interest payments. Even if the new rate is lower, the additional 5 years of a large balance can easily cost more total interest than you save from the rate reduction.

Example: a $350,000 remaining balance at 6.5% with 25 years left has a total future interest obligation of ~$346k. Refinancing to a 30-year at 6.0% lowers the monthly payment by $118 but costs ~$376k in total future interest — $30k more total, despite the lower rate.

When a cash-out refi makes sense

• Rate drop of 1%+ with long remaining horizon: Meaningful monthly savings, sufficient time to break even and realize net savings.
• Funding a high-ROI investment: Using cash-out proceeds to purchase a rental property at 8% cap rate when your new mortgage rate is 6.5% creates positive leverage. This is the classic real estate investor move.
• Consolidating high-rate debt: Replacing 24% credit card debt with 6.5% mortgage debt dramatically reduces interest cost — but only if you don't accumulate new credit card debt afterward.
• Removing PMI: If you originally put down less than 20%, a refinance once equity reaches 20%+ eliminates PMI, potentially saving $100–$200/month.

Tax treatment post-TCJA (2018)

Under the Tax Cuts and Jobs Act, mortgage interest is deductible only on acquisition debt — debt used to buy, build, or substantially improve the home. Interest on the cash-out portion is deductible only if proceeds were used for home improvements. Cash-out used for debt consolidation, education, investments, or living expenses produces non-deductible interest. Given the higher standard deduction post-TCJA, fewer than 10% of taxpayers itemize, making the mortgage interest deduction irrelevant for most homeowners regardless of use.