For a 20-person seed-stage startup, the two strongest options are Ramp and Brex — both drop the personal guarantee and underwrite on your cash and revenue rather than personal credit.12

Ramp is usually the better default at this size: its core plan is $0 with no per-seat fee and a flat 1.5% cash back, so there's nothing to optimize and nothing to pay as you add the next ten hires.2 Brex makes sense if you spend heavily on travel and software and will use the up-to-8× points program, or if you want cards, bill pay and banking on one platform as you scale.1

If you already keep your operating cash in Mercury, its IO card is the simplest add-on — but it's USD-only, so skip it if you spend internationally.3