The situation
A mid-market AP automation platform processing approximately $180M in annual payment volume had been operating a virtual card program through a BaaS-provided card infrastructure for three years. The program was generating approximately $850K annually in VCard interchange — meaningful, but significantly below what the volume should have produced.
An economics audit identified three compounding leakage sources: the BaaS middleware was capturing approximately 45% of gross interchange (leaving the platform with 55% of what flowed through), the program was running on a consumer-grade BIN category rather than a commercial purchasing card BIN, and the VCard STP rate had plateaued at 14% — well below industry benchmarks for programs at this volume.
The architecture gaps
At $180M annual volume and 175 bps gross interchange on a commercial purchasing card BIN, the theoretical annual interchange was approximately $3.15M. The platform was generating $850K — a $2.3M gap. The BaaS share accounted for approximately $1.1M of that. The BIN category difference accounted for approximately $600K. The low STP rate — routing eligible payments to ACH instead of VCard — accounted for the remaining $600K.
No single gap was individually obvious at program launch. The BIN selection happened by default when the BaaS provider provisioned the card program. The STP rate plateau was visible in operational reporting but not connected to its revenue consequence. The BaaS economics share was in the contract but not modeled against the volume trajectory.
What changed
The migration had three tracks running in parallel. First, the compliance infrastructure: the platform built a complete BSA/AML program, KYB/KYC processes, and bank reporting framework — prerequisites for the direct bank conversation. This took approximately 10 weeks.
Second, the sponsor bank relationship: the platform identified and onboarded a sponsor bank that provided commercial purchasing card BIN access and a direct economics agreement without middleware share. The bank onboarding process took approximately 9 months concurrent with the compliance build.
Third, supplier enablement: the platform launched a dedicated VCard enrollment campaign, hired a supplier enablement manager, and deployed AR integration tools that improved STP rates. This ran as an ongoing program rather than a one-time launch activity.
The outcome
Fourteen months after the architecture decision, the platform was generating approximately $2.05M annually — a $1.2M improvement over the prior program. The BIN upgrade alone added approximately $580K. Eliminating the BaaS middleware share added approximately $480K. The STP rate improved from 14% to 22% in the first year of the supplier enablement program, contributing approximately $140K in additional interchange from volume that previously routed to ACH.
The supplier enablement program is ongoing — the platform is targeting 35% STP within 24 months of program launch, which would generate an additional $380K annually at current payment volume.