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Appliance delay timers explained: "starts in" vs "finishes in"

Last updated: 10 August 2026

Here's a question that catches almost everyone out. Your washing machine's cycle takes two and a half hours. You press the delay button until the display shows 7:00. When does the machine start? If you said "in seven hours" — maybe. On a lot of machines, the honest answer is "in four and a half hours", and that difference is exactly enough to land your wash in the wrong electricity prices.

The three kinds of delay timer

Appliance manufacturers never agreed on what a delay timer means, so three different conventions ended up in our kitchens:

• Delay to start. The number is how long the machine waits before switching on. A delay of 3 means it starts in three hours and finishes three hours plus one cycle later. Most dishwashers work this way, usually in one-hour steps.
• Delay to finish. The number is when the cycle will be done. A display of 7:00 means "your washing will be ready in seven hours" — so the machine quietly sits idle for seven hours minus the cycle length, then starts on its own. Many washing machines and washer-dryers use this convention, because "when will my clothes be ready?" is the question the manufacturer thinks you're asking.
• Fixed options. No dial at all — just a few buttons, commonly 3h, 6h and 12h (or a similar set). Tumble dryers often do this. You can't aim precisely; you can only pick the least-bad option.

Why finish-anchored timers trip people up on Agile

On a flat tariff the confusion is harmless — the wash costs the same whenever it runs. On Octopus Agile, where prices change every half hour, it's the difference between a cheap wash and an expensive one.

Work the example properly. It's 9pm. Tonight's cheapest window is 2am–4:30am. Your machine's cycle is 2 hours 30 minutes and its timer is finish-anchored, stepping in one-hour presses:

• You want the machine running from 2am to 4:30am — so you want it to finish at 4:30am, which is 7½ hours away.
• The display steps in whole hours, so the closest settings are 7:00 (runs 1:30–4:00am) or 8:00 (runs 2:30–5:00am).
• Which is cheaper depends on the exact half-hourly prices either side of the window — the kind of comparison that's tedious by hand and instant for software.

Now imagine you'd treated that finish-anchored display as a start delay. Setting "7:00" expecting a 4am start would actually run the machine 1:30am–4:00am — fine tonight, but make the same mistake in the other direction and a cycle you aimed at midnight runs straight through the 4–7pm evening peak instead, at several times the price.

How to tell which kind your machine is

• Read the display wording. "End", "Ready in", "Finish in" or a flag icon means finish-anchored. "Start delay", "Delay start" or an hourglass usually means start-anchored.
• Do the one-press test. Set the smallest possible delay. If the display's number equals the cycle time plus the delay, it's finish-anchored. If it shows just the delay, it's start-anchored.
• Check the manual — search the model number and "delay". The section is usually one paragraph and settles it immediately.

Let the software do the arithmetic

This is the exact problem Cheap Hours was built to remove. You tell it once how your machine's timer works — start-anchored, finish-anchored, or fixed options — and its cycle length. It then scores every setting the machine actually offers against the live half-hourly prices for your region, and answers in the machine's own language: "press the delay button until the display shows 7:00", along with the real start time, finish time, and what the run will cost compared to the expensive alternative.

There's a subtler win, too. Because tomorrow's prices only appear at around 4pm, a long delay set in the morning is aiming blind. When the timer's range can't reach the cheapest published window yet, Cheap Hours says so — and tells you when to come back and what to set then.

Keep reading

• The cheapest time to run a washing machine — finish-anchored timers in practice
• The cheapest time to run a dishwasher — the easy case: start delays in hour steps
• The cheapest time to run a tumble dryer — making the best of 3h / 6h / 12h buttons