How to pay with bitcoin: Lightning, fees and delays explained

Most people who give up after a failed first payment tripped on the same thing: they used the wrong network without knowing there were two. This guide explains which to choose and why, before moving on to fees and wallets.

If you are looking for where to pay instead, the guide to where to spend bitcoin covers that.

Two networks, not one

Bitcoin runs on a blockchain: a public ledger where every transaction is recorded, then validated by the network. That validation takes time by design — one block every ten minutes on average.

It is an excellent system for moving large sums irreversibly. It is a poor system for buying coffee: nobody wants to wait ten minutes at a till, and on-chain fees bear no relation to the amount being sent. Sending three euros can cost as much as sending three thousand.

The Lightning Network solves exactly that. It is a layer built on top of Bitcoin where payments move off the main chain and only touch it when a channel opens and closes. The result: a payment confirmed in one or two seconds, for fees counted in cents whatever the amount.

That is why nearly every recently equipped business expects Lightning. On every listing in the directory the two appear separately — not as a detail: a business showing "Bitcoin" without "Lightning" will make you wait.

Fees, without the folklore

Three misunderstandings come up constantly.

"Fees depend on the amount." False on-chain: they depend on the size of the transaction in bytes and on how busy the network is when you send it. A small payment can therefore cost proportionally a great deal. On Lightning fees are genuinely proportional, but so small that the question stops mattering.

"It's free." Also no. Opening a Lightning channel is an on-chain transaction, so it costs. Custodial wallets spare you that step by managing channels for you — which is the trade-off covered below.

"The business pays a commission like with a card." This is precisely the argument that convinces many merchants: where a card takes between 1 and 3 % of the amount, a Lightning payment costs them a fraction of a cent. On thin margins that gap is decisive — and it explains why some online merchants offer a discount for paying in crypto.

Choosing a wallet

This is the decision that matters most, and it comes down to a single trade-off: who holds the keys.

Custodial wallets. A service holds your funds and lets you use them. Setup takes two minutes, there are no channels to manage, and paying works first time. In exchange you depend entirely on that service: if it shuts down, freezes your account or is breached, your funds go with it. It is the sensible choice for learning, and for small everyday spending money.

Non-custodial wallets. You hold the keys, and nobody can separate you from your funds. In exchange, channel management is at least partly yours, and a lost recovery phrase means lost funds — no recourse, no support line. This is the right choice as soon as the amounts matter.

The practical criterion, before any of that: does the wallet do Lightning at all? Plenty of well-known wallets are on-chain only. Check before you set off, not at the counter.

A payment, step by step

Five steps, about thirty seconds in total.

1. Say you are paying in crypto before they ring it up. On many terminals the payment method is chosen at the start and cannot be changed after.
2. The business generates a QR code for the exact amount. On Lightning that code lives for a few minutes.
3. You scan it with your wallet, which shows the amount, the fee and the recipient. This is the moment to check the sum — afterwards it is irreversible.
4. You confirm. On Lightning the confirmation lands before you have put your phone away. On-chain, the wait begins.
5. The business sees it arrive on their terminal. Some ask to see your screen, which proves nothing: their terminal is what counts.

What can go wrong

The QR code has expired. The most common case. A Lightning invoice lives for a few minutes; ask for a new one, it is instant.

The payment stays "pending". Almost always an on-chain payment sent with fees too low while the network was busy. It will go through eventually, but not within a checkout queue — which is the whole point of Lightning.

The amount does not match. Some gateways lock the rate when the QR is generated, others at confirmation. On a coffee the gap is invisible; on a hotel night it shows. Ask which applies when the amount matters.

Your wallet refuses to send. On Lightning, usually a capacity problem: the channel has too little on the right side. A custodial wallet handles that for you; a non-custodial one needs you to have thought about it beforehand.

And then

The best way to learn is still a small first payment somewhere you know it works. Restaurants and cafés are the most forgiving: the amount is small, the staff are used to it, and a mistake costs nothing.

Find one near you on the map, filtering on Lightning if that is all your wallet does. And once the payment has gone through, confirm the listing: that is what tells the next visitor the place genuinely works.