How to scale OFAC screening for high transaction volume

Scaling screening to 100K or more transactions a day is about making each check fast, cheap, and safe to run in parallel.

TL;DR

TL;DR: Use connection pooling, async calls, and caching of clean results so screening keeps pace with high volume without becoming a bottleneck or a silent failure point.

Connection pooling and async

Keep a pool of persistent connections to the screening service instead of opening a new one per request, and run checks asynchronously so a slow response cannot stall the payment pipeline. A screening API that answers in under 100 ms keeps per-transaction overhead low even at scale.

Caching and infrastructure

Cache recently seen clean results for a short window to reduce repeat lookups, but always fail closed on any uncertainty. A flagged or unknown result must block. Scale your screening service horizontally alongside your payment workers rather than behind a single shared queue.

Cost and reliability

Pick pricing that scales with volume. SanctionsAI offers a free tier of 5 checks per day, Dev at $19 per month for 10,000 checks, Pro at $99 per month for 100,000 checks, and $0.05 per check via x402. It screens 947 OFAC-listed wallets and 19,218 SDN names, synced hourly.