Affiniti

Affiniti (Affiniti Finance, Inc.) is a financial technology company serving small and medium-sized businesses in the United States. Its product set includes a business credit card with up to 2.1% unlimited cash back, a checking account paying up to 3% APY with FDIC insurance coverage available up to $3 million through partner bank Thread Bank, expense management, bill pay and accounting automation that produces native QuickBooks (.qbo) files. Card services are provided by Patriot Bank NA. Affiniti is not itself a bank. A "live financial intelligence" product that analyzes a business and its industry in real time to surface cash optimization insights is listed on the company's site as launching soon.

The company targets traditional "main street" operators — independent pharmacies, HVAC firms, auto dealerships and repair shops, medical and podiatry practices, coffee shops, cleaning services, fitness centers and coin laundries — most of which lack a dedicated finance team. Its revolving credit card offers an interest-free period of up to 55 days with the ability to carry balances, which the company positions as suited to industries such as healthcare where insurance reimbursement can take more than 70 days. Underwriting considers both the business owner's personal credit and the overall health of the business rather than relying on cash flow or venture backing alone. Affiniti also offers short-term loans of up to 90 days against invoices.

Cofounders Aaron Bai and Sahil Phadnis describe their approach as "v3" fintech: after traditional banks and cards (v1) and design-led spend platforms such as Brex and Ramp (v2), software that advises the end user and delivers analytics. Building on that thesis, the company is developing an "AI CFO" agent intended to handle banking, bill pay, sales and other finance functions, tuned by vertical (healthcare, automotive and others), with large language models also used internally to assess business financial health.

Founding story

Aaron Bai and Sahil Phadnis met while attending UC Berkeley. Both had previously worked with small businesses — Bai helping local businesses in Southern California with technology and marketing, Phadnis building websites, SEO and e-commerce for clients in North Carolina — and observed a gap between Silicon Valley technology and the largely paper-based systems used by traditional small firms. They founded Affiniti to serve those businesses rather than going through an accelerator such as Y Combinator, using their Berkeley network for introductions to investors.

Business model

Affiniti sells a bundled financial operations platform to SMBs, issuing credit cards and deposit accounts through partner banks (Thread Bank for banking, Patriot Bank NA for card services) while providing the software layer for expense management, bill pay, accounting automation and analytics. Distribution leans on partnerships with industry trade associations, which also unlock member benefits such as group purchasing discounts.

The company earns most of its revenue from transaction interchange fees on card spend, supplemented by SaaS software sales and interest income on short-term (up to 90-day) invoice-backed loans.

Traction

In its first 14 months the company went from zero to 1,800 customers and roughly $20 million per month in transaction volume, with founders projecting $1 billion in annual transaction volume by the end of 2025. Revenue was reported to have grown about tenfold in a year from a $1 million base. A pharmacy customer, Cascadia Pharmacy Group, said it had onboarded 40 of its pharmacies onto the platform.

Latest developments

In May 2025 Affiniti closed a $17 million Series A led by SignalFire, six months after its seed round, and said it would use the capital to add banking, bill pay, cash flow analytics and ERP/point-of-sale integrations. The company is developing vertical-specific AI agents marketed as an "AI CFO," and its website lists a live financial intelligence product as launching soon.