Most of Your Vendor Spend Belongs on a Card

A founder I work with runs a 45-person services firm with about $310K in monthly vendor spend. Software, contractors, marketing platforms, travel, the usual mix. Almost all of it paid by ACH because that's how the bookkeeper had always done it.

I asked her what she was earning on AP. She thought I meant interest on a payable balance, which isn't a thing. Card rebates were what I meant. She wasn't earning any.

Her cards covered office supplies and conference travel. Maybe $8K a month. The other $300K moved through ACH or wire because nobody had set up the workflow to do otherwise. Annualized rebate she was leaving on the table at a 1.25% card rate on the card-eligible portion: roughly $40,000.

What's available

Most corporate cards from Brex, Ramp, Mercury, and the bigger banks pay 1 to 1.5% cashback on standard categories. Higher tiers go to 2% on specific spend. Virtual card platforms like Bill.com and Coupa issue single-use numbers that replace ACH for vendors willing to take cards.

Rebates aren't the whole story. Each virtual card has a fixed amount and a fixed expiry, locked to one vendor. If a vendor's billing system gets compromised, the card dies in seven days regardless of what you do. The security case used to be the lead argument. Treasury is the bigger one now.

For a company with $200K to $500K of monthly vendor spend, moving 50-70% of it onto cards returns $20K to $60K a year. No new headcount. No new tool category. No vendor negotiation. Most accept cards if you ask. Some charge a small surcharge that nets out below the rebate anyway.

Card rebates aren't a perks program. They're a treasury yield on cash that already moves through the business.

Why most founders skip it

Three reasons keep showing up.

Bookkeeper inertia is procedural. ACH is set up. Cards mean reconciling statements, matching virtual card numbers to invoices. Updating the AP system. It's a one-time setup cost paid in dollars by accountants who weren't asked to think about yield.

Surcharge fear is the second. Some vendors charge 2-3% to accept cards. At a 1.5% rebate, that's a net loss. True for those specific vendors. For the others, surcharges are zero or absorbed. A vendor list with two columns handles it: who surcharges, who doesn't. ACH for the first group, card for the second.

Credit-line worry is the third. Founders see "card" and assume credit risk against a personal limit. Modern corporate cards aren't credit cards. Brex and Ramp run as charge cards backed by your bank balance. Cash leaves on a schedule you set. Limit isn't capped at a personal credit line.

How to capture it

For a 30-50 person company, the conversion takes a few weeks of part-time finance work.

Pull last quarter's AP. Sort vendors by spend. Mark which accept cards. Software, marketing platforms, and most contractors do. Move those payments. Keep ACH for payroll and rent.

Track the rebate as a line item, not a footnote. If you're not seeing $1,500 to $3,000 a month in rebate credits within 90 days, the conversion isn't done.

Most growing companies pay vendors the way they always have. Paying deliberately funds a hire a year.