Posted 5 months ago

Renting vs Buying With an Assumable Mortgage

At today's 7% rates, renting is often cheaper than buying. But an assumable mortgage at 2.5% completely changes the math. Let me show you.

The Standard Rent vs. Buy Math (at 7%)

Take a $400,000 home at 7%:

Monthly mortgage (P&I): $2,661
Property taxes: ~$350/month
Insurance: ~$150/month
Maintenance: ~$300/month
Total monthly cost: ~$3,461

Average rent for a similar home in Colorado: $2,600. At 7%, buying costs about $800 more per month than renting. Add the $20,000+ down payment and closing costs, and it takes years to break even.

The Assumable Mortgage Math (at 2.75%)

Same $400,000 home, assumed at 2.75%:

Monthly mortgage (P&I): $1,632
Property taxes: ~$350/month
Insurance: ~$150/month
Maintenance: ~$300/month
Total monthly cost: ~$2,432

Now buying is cheaper than renting by about $170/month — and you're building equity with a fixed payment while rents increase every year.

The Equity Advantage

When you rent, your payment builds your landlord's wealth. When you buy with an assumable mortgage at 2.75%, a significant portion of your payment goes to principal from day one. After 10 years, you've built roughly $100,000 in equity just from principal payments, not counting appreciation. Renters have zero equity after 10 years.

The Rent Escalation Factor

Rents go up. Your assumed mortgage payment stays fixed. If your rent starts at $2,600 today with 3% annual increases, in 10 years you'll pay $3,225/month. In 20 years: $4,335/month. Your assumed mortgage payment? Still $1,632. Every year, the gap widens.

The Total Wealth Comparison (10 Years)

Renter:

Total rent paid: ~$318,000 (with 3% annual increases)
Equity built: $0
Net cost: $318,000

Assumable Mortgage Buyer:

Total housing payments: ~$292,000 (fixed)
Equity built: ~$100,000 (from payments alone)
Home appreciation (3%/year): ~$137,000
Effective net cost after equity gains: ~$55,000

The renter spent more and has nothing to show for it. The buyer spent less and built $237,000 in equity.

Who Should Still Rent?

Renting still makes sense if you're staying less than 3 years, can't qualify for the assumption, can't cover the equity gap, need mobility for career or personal reasons, or are in a market with very low rents relative to home prices. But for anyone planning to stay 3+ years who can qualify and cover the equity gap, an assumable mortgage is the clear financial winner.

Ready to Find an Assumable Mortgage in Colorado?

Browse available listings or schedule a free call with Ryan Thomson, Colorado's leading assumable mortgage specialist.

Browse Homes | Schedule a Call | (719) 624-3472

Ryan Thomson, The Assumable Guy | https://assumableguy.com/blog/renting-vs-buying-assumable-mortgage