The card reader has an error on its screen, there's a line forming, and the person at the front is already holding their card out. This is the worst moment to start rebooting things at random — and the right moment to spend two calm minutes finding out which of three things is actually broken: the terminal, the internet, or the payment processor.
The two-minute triage
- Is it one terminal or all of them? One register down while the others work fine means the problem is that device — skip to the next section. Everything down at once points at your network or your processor.
- Does anything else have internet? Take a phone, switch its cellular data off, join the store Wi-Fi and load any website. If nothing loads, your internet is down and the POS is an innocent bystander. If pages load normally, the connection is fine and the fault sits with the terminal, the way your network is laid out, or the processor.
- Internet fine, every terminal down? Then it's probably upstream. Square, Clover and Toast — the systems behind many shop and restaurant counters — each publish a public status page; search the brand name plus "status" from your phone. If they're reporting an outage, nothing on your side needs fixing. Switch to offline mode or your backup plan and keep serving.
One terminal down: the usual suspects
- Restart it properly. A full power-off and back on, not a tap of the sleep button. Payment terminals run for months without a reboot and accumulate the same clutter any computer does.
- Check the physical layer. Ethernet cable clicked home at both ends, terminal seated squarely in its cradle, power brick actually delivering power. A reader that pairs over Bluetooth should be charged, close to its tablet, and re-paired if it has dropped.
- Confirm which network it joined. A terminal that quietly reconnected to the wrong Wi-Fi looks healthy and fails anyway — more on that two sections down.
- Look for a stuck update. Terminals occasionally hang mid-update. A restart usually clears it; each brand's support site lists its own recovery steps if it doesn't.
The whole internet is down
Unplug the modem and the router, wait thirty seconds, then start the modem first and give it two full minutes before powering the router. Starting them in the wrong order is why "I already rebooted it" so often hasn't worked. While they boot, check your provider's outage page from a phone on cellular data.
If the outage is on the provider's side, your card readers are down until the line comes back — unless you have a second path to the internet. A failover router with a cellular SIM switches over by itself and turns a provider outage into a non-event at the counter; our guide to backup internet for business covers how it's wired and what to weigh up. Until then, offline mode below is the bridge.
Someone changed the Wi-Fi
A surprising share of POS outages begin with a change nobody connected to payments: the ISP swapped the router, somebody changed the Wi-Fi password, a new access point went up, a guest network was added over the weekend.
- New router or new password. Every terminal is still trying to join a network that no longer exists. Each one has to be joined to the new network by hand — there is no shortcut.
- Terminal on the guest network. Guest Wi-Fi is deliberately walled off, so a terminal that hops onto it may reach the internet but not your receipt printer or POS hub. Card terminals are like printers: after any network change they will cheerfully join the one network that can't reach anything. Setting up guest Wi-Fi properly keeps customers and payments on separate rails without this trap.
- VLANs and static addresses. If your POS lives on its own network segment — it should — a replacement router knows nothing about those rules, and terminals with fixed addresses may now be on the wrong subnet. This is the one cause on this page that genuinely rewards a professional; a tech on Koadi can usually untangle it over a screen-share in under an hour. How a small office network should be put together explains the segmentation.
Offline mode, honestly
Square, Clover and Toast all offer an offline, store-and-forward mode: the terminal encrypts the card details, stores them on the device, and sends them for authorization once the connection returns. It keeps the line moving, and you should know exactly what you're agreeing to when you switch it on.
The card is never checked at the moment of sale. A card that is over its limit, cancelled or stolen sails through the tap and declines hours later, after the customer has left with the goods — and that loss is yours, not the processor's.
The limits, as of September 2026:
- Square's pending offline payments expire if the device isn't reconnected within 72 hours, and its terms make you responsible for offline payments that expire, decline or are disputed.
- Clover stops accepting offline payments after seven consecutive days without a connection, and a payment taken offline can still decline when it finally processes.
- Toast stores offline card payments encrypted on the device and submits them once it's back online, and advises against operating offline for long stretches.
Use it deliberately: set the per-transaction cap the settings offer, keep it to modest amounts, and reconnect the moment you can — not at closing time.
The backup plan every counter needs
All of this gets decided on a quiet Tuesday morning, not mid-rush:
- A second way online. A cellular failover router is the proper fix. A phone hotspot the terminals have already saved is the cheap one — it only helps if the terminals knew the hotspot before the outage.
- Manual entry, sparingly. Your processor's web dashboard has a virtual terminal for keying in card numbers from any browser. Keyed payments cost more per transaction and lose the fraud protection a chip gives you — acceptable for one afternoon, a bad habit after that. Never write card numbers on paper to enter later.
- A printed one-page procedure taped inside the counter: how to turn on offline mode and the cap you chose, the hotspot name and password, the processor's status page address, and who to call. The day it's needed, the person on shift may not be you.
- Cash still works. A float in the drawer and a sign pointing at the nearest ATM has rescued plenty of lunch services.
Prevention is mostly network hygiene: wire the terminals with ethernet where you can, keep payments off the guest network, and label the router so the next quick change doesn't take the tills down with it.
Getting it fixed while the line keeps moving
If the triage points at your network — or you'd rather someone else did the pointing — post the problem free on Koadi. Vetted, identity-verified technicians pick it up; you set a fixed price or take bids, and payment sits in escrow until you approve the fix. Most POS connectivity faults are fixed remotely over a screen-share, anywhere in the US, evenings and weekends included, and when the router or cabling needs hands, a local vetted tech comes to you. Koadi also builds and repairs small-business networks end to end, so the fix can include making sure this doesn't happen again. Post it now and keep serving.