19:41. Eleven tables seated, four mains away, two card payments part-authorised. The lights go and the room does that half-second of silence before someone laughs. What happens next was decided months earlier, and almost none of it by software.
The first ninety seconds
If the till is on a UPS, it is awake and still holds every open table. If the router is on the same UPS, the floor tablets and the second till can reach it. Protect only the till — the common half-measure — and you have one working machine and a floor of dead tablets. Put the router on battery: it draws almost nothing and it is the difference between one operator and a working shop. A small unit carrying the till, the router and one printer for twenty minutes is doing its job; the fryer and the walk-in are not on it.
Kitchen display screens go dark with the power; printed tickets do not. If the kitchen runs on gas and the tickets are already on the rail, service continues. If it runs on induction and screens, the outage is a kitchen problem before it is a till problem.
Taking money while it is dark
Card terminals need both power and a line, and no point of sale can authorise on their behalf. Cash and any offline-capable tender carry on. Guests who only have a card either wait or leave details and settle later — a decision the owner makes in advance, not a waiter at the pass.
This is a different failure from the one people prepare for. A network outage with the power on is a much softer problem, covered separately in what happens when the internet goes down. Do not let a supplier answer the power question with the offline-mode answer.
What the slip still has to say
South Africa has no fiscal device mandate, so there is no certified box to fail. What there is, is the VAT Act, and SARS is specific about what a tax invoice contains. VAT is 15%. It nearly moved — a rise to 15.5% was set for 1 May 2025 and a further step to 16% proposed — but the increase was withdrawn that April.
Above R5,000 including VAT a full tax invoice is required: the words Tax Invoice, VAT Invoice or Invoice; supplier name, address and VAT number; recipient name, address and VAT number; a serial number and date of issue; a description of the goods or services; the quantity or volume; and the value, the tax charged and the total consideration. At R5,000 or less an abridged tax invoice may be issued, dropping the recipient’s details. At R50 or less an ordinary till slip showing the VAT will do. A tax invoice must be issued within 21 days of the supply.
A large function bill crosses R5,000 easily, and it is the bill most likely to be written by hand at the worst moment. If staff cannot capture a VAT number when the screen is dark, decide now whether that function takes cash at the door or an invoice in the morning.
The hour after the power comes back
Everything written on paper has to go into the system, and this is where outages turn into shrinkage. Enter transactions with the time they actually happened, not the time you are typing, so the trading pattern stays honest. And keep the physical slips, numbered, until the day is reconciled and signed off — they are the only evidence the re-keyed batch matches what was sold.
A manual batch is the softest target in the business — transactions with no electronic origin. Tighten permissions before you need them: who may enter a backdated sale, who may adjust one, and whether either is logged. Same control surface as stopping staff from voiding orders and changing prices. The end-of-day cash-up on a power-cut day should be slower and more sceptical than usual.
What has actually changed by 2026
National load shedding has stopped. Eskom marked a full year without a single interruption on 16 May 2026 and carried the 2026 winter through without implementing it. What has not stopped is load reduction, a different animal — localised, applied to overloaded feeders, usually in the morning and evening peaks, and often without the warning a load shedding schedule gave. Eskom expected to clear most affected feeders during 2026 and the rest into 2027; municipal faults still cut suburbs independently.
So the planning assumption is not the 2023 one. You will probably not lose four hours to a published schedule. You may still lose forty minutes at 18:30 with no notice, which is worse in one respect, because you cannot roster around it.
Worth watching rather than acting on: SARS published a VAT Modernisation consultation paper in August 2026 proposing e-invoicing and near real-time reporting, comments due 16 October 2026, phased from large B2B taxpayers with consumer-facing retail last and implementation indicated from around 2030. Nothing changes for your till this year. For VAT registration and filing, our sister site yunyafx.com goes deeper.
What we will not tell you
That we are certified for anything in South Africa — there is nothing to be certified for today, and that changes if the modernisation programme lands. What the system supports for your country we answer specifically before you buy, not in one sentence covering 100+ countries.
Checked against the sources named above on 2026-09-20. Rules and platform terms change — confirm anything tax-related with a local accountant before you rely on it.
