SOFR Floater Calculator

SOFR floaters price over an index plus spread. This calculator computes all-in coupon and monthly debt service.

Balance

Current SOFR %

Spread over SOFR (bps)

Interest-only?

Amort years (if not IO)

All-in coupon %

7.100%

Monthly debt service

$71,000

Annual debt service

$852,000

How the math works

All-in = SOFR + spread. Debt service = interest-only (balance × coupon) or amortizing payment.

Floating-rate debt service can swing 30-50% year-over-year in volatile cycles. Model worst-case monthly debt service before accepting — a deal that pencils only at today's SOFR will fail under reset.

How to Use

Enter loan balance.
Enter current SOFR.
Enter spread over SOFR.
Enter interest-only switch.
Enter amortization years.
Read all-in coupon and debt service.

Frequently Asked Questions

Term vs daily SOFR?

Term SOFR (1-month, 3-month) is common on commercial loans. Daily SOFR (SOFR average) is standard on syndicated bank loans. Term is simpler; daily has less tenor risk but more operational complexity.

Typical spreads?

Multifamily SOFR + 200-275 bps at 65% LTV. Office bridge SOFR + 400-550 bps. Construction SOFR + 300-450 bps. Spread widens with LTV, asset risk, and sponsor quality.

Floor vs cap?

Many agreements include a SOFR floor (usually 25-100 bps) to prevent ultra-low coupons. Cap is sponsor-side protection at higher level. Floor increases effective coupon in low-rate environments.

How does this interact with the rest of the capital stack?

Each tier of the stack affects the next. Senior debt constrains LTC and DSCR. Mezz and pref consume equity spread. Interest rate hedges protect DSCR but cost premium. Always model the full stack holistically — optimizing one tier alone often degrades another. Institutional underwriters run three or four scenarios across the stack before committing capital.