Solving Card Declines: Time-Locked Pre-Authorization Escrows
By Protocol Engineering · June 1, 2026 · 5 min read
The card hold problem
Self-custodial debit cards frequently fail at gas pumps, hotels and car rental agencies. Traditional card networks require a pre-authorization hold (for example, locking $150 at the pump before fuel is dispensed). Because on-chain smart wallets can't easily support temporary hold states, these transactions are usually declined automatically.
The Furlpay escrow solution
To solve this, Furlpay developed the Pre-Authorization Escrow Contract. When a merchant requests a hold, our backend creates an isolated, time-locked escrow and moves the hold amount from the user's wallet into it.
[ Merchant pre-auth ] ──> [ Time-locked Escrow ] ──(final amount)──> [ Merchant ]
│
└──(remainder / 7-day expiry)──> [ User Wallet ]Once the final purchase amount settles, the escrow releases that amount to the merchant and returns the remaining balance to the user. If the merchant never claims the funds, the escrow automatically expires after 7 days, returning the entire deposit to the user — no stuck holds, no manual reversals.
Protocol Engineering
Furlpay
Written by the Furlpay team — engineers and compliance specialists building an on-chain financial operating system for stablecoin payments, travel, and investing on Arbitrum.
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