Your card keeps getting declined by US dev tools. Here is what is actually happening

TL;DR: SaaS declines outside the US are almost always a risk decision, not a balance problem. Fix the billing address first, then use a card built for global online spend.

If you build outside the US, you know the moment. You pick a plan for Cursor, GitHub Copilot, or Vercel, hit Subscribe, and get "Your card was declined." No reason given. The same card works at the grocery store.

I dug into this as a developer, and now I work on payments. Here is what is actually happening, and what fixes it.

Disclosure: I work on Fizen, one of the crypto-card options below. I included the tools I would recommend either way.

Why it gets declined

It is rarely "no money." Most US SaaS bill through Stripe, so a decline is a risk score, not a balance check. The usual causes:

• AVS mismatch. Stripe checks your billing ZIP against your bank. Non-US address formats fail this quietly.
• BIN blocking. Your card's first digits encode the issuing country. Some Radar rules down-rank or block specific countries.
• Prepaid and virtual filters. Many SaaS block prepaid BINs to stop trial abuse. A lot of "virtual cards" share those BINs.
• 3DS friction. Your bank wants an OTP the checkout never triggers, so the auth fails.

Stripe returns a decline_code. If the tool surfaces it (or support tells you), incorrect_zip vs card_not_supported vs do_not_honor points straight at the cause. That one string saves hours.

The fixes, lowest effort first

1. Fix the free stuff. Match the billing address exactly to what your bank has on file. Turn on international and online payments in your bank app. Retry in incognito to clear a device flag.

2. Use a card built for global online spend. Wise and Revolut behave well with USD SaaS and show the real FX rate. Mercury works if you have a US entity. Privacy.com is great but US only.

3. If you already hold stablecoins, a crypto-funded card. Fizen, Gnosis Pay, and RedotPay let you fund a Visa with USDT. What matters at checkout: it carries a real Visa BIN, you can spin up a virtual card per subscription, and there is no FX markup on recurring USD billing. Caveats worth saying out loud: you still pass KYC, a merchant can still block the BIN, and you are holding USDT, which is a custody choice, not free money.

What I run

One clean card with a correct billing address for strict merchants. One virtual card for the ones that reject the first. I log the decline_code every time. After two or three failures the pattern for your country is obvious and you stop guessing.

Stuck on a specific tool? Drop the tool and your country in the comments and I will tell you which lane usually clears it.

I keep a longer writeup on the crypto-card side, including limits and which merchants block which BINs, here. The fixes above stand on their own.

Comments

[John Frandsen]

Great breakdown of the card-side mechanics. The AVS/BIN/3DS taxonomy is exactly right — most developers outside the US hit at least two of these simultaneously and can't tell which one is the actual blocker.

One angle worth adding for European developers: the entire card-decline problem is structurally avoidable if the merchant accepts Pay by Bank (Payment Initiation Services under PSD2). Instead of routing through Visa/Mastercard, the payment goes directly from your bank account to the merchant via an open banking API call. No card BIN to block, no AVS mismatch (the bank authenticates you via SCA — Strong Customer Authentication — as part of the flow), and no prepaid/virtual card filter to trip.

The tradeoffs are real though:

• Merchant adoption is the bottleneck. Most US SaaS still only accepts cards. Pay by Bank is growing fast in the UK and EU (companies like TrueLayer, GoCardless, and Tink provide the rails), but you won't see it on Cursor or Vercel billing pages yet.
• Payments are irrevocable. Unlike card chargebacks, a PIS payment settles immediately. Great for merchants (no fraud risk), but means you need to trust the subscription model.
• Cross-border limits. PIS works within SEPA. If you're paying a US-based SaaS that doesn't have an EU payment entity, it won't help — the card is still your fallback.

The fee economics are why this matters long-term: PIS transactions typically cost merchants 0.1–0.5% vs 2.9% + $0.30 for cards. As more SaaS platforms add Pay by Bank as a payment option (Stripe already supports it in the UK via their Treasury product), the card-decline problem becomes a non-issue for European customers.

Until then, the card fixes in this article are the practical answer. Logging the decline_code is especially good advice — do_not_honor from an Indian or Brazilian BIN means something very different than incorrect_zip from a German one.

[Eugene]

Thanks for breaking this down, this is one of the clearest explanations I’ve seen on why non‑US cards get blocked by SaaS tools. The AVS mismatch and BIN blocking are definitely the biggest silent killers, and your tip about logging the decline_code is gold.

For anyone stuck on the billing address part, I’d add that getting your exact address format from your bank’s records is step zero. Some people also overlook that their bank’s system may abbreviate street names differently than they type. Also, if you’re managing multiple cards or need to verify balances before retrying, I recently came across a handy tool that helps with that, you can visit website to check your card balance quickly, which at least rules out the “insufficient funds” confusion before you start chasing risk flags.

Your crypto‑card suggestions are solid too, especially the virtual card per subscription idea. Appreciate the practical fixes, saved this for reference.