A sensible time to start using a SAD lamp in the UK is October, when many people begin waking before sunrise, and a sensible time to stop is late February or March, when it is light again by the time you get up. There is no official date. When to start using a SAD lamp depends on where you live, when your alarm goes off and how you feel as the days shorten. This guide goes month by month, using real sunrise and sunset times.
When do UK mornings get dark?
The simplest test is to compare sunrise with your alarm. If you get up in the dark, morning daylight is not available, and that is when a bright-light lamp (a light therapy lamp or light box) has a job to do. The table gives sunrise and sunset times (local time, approximate to the minute) for five UK cities.
| Date | London | Manchester | Edinburgh | Belfast | Cardiff |
|---|---|---|---|---|---|
| 1 Oct 2026 | 07:01 / 18:38 | 07:10 / 18:45 | 07:15 / 18:47 | 07:26 / 18:59 | 07:13 / 18:50 |
| 24 Oct 2026 (day before clocks change) | 07:40 / 17:48 | 07:52 / 17:52 | 08:02 / 17:50 | 08:10 / 18:04 | 07:52 / 18:00 |
| 25 Oct 2026 (after clocks go back) | 06:41 / 16:46 | 06:54 / 16:50 | 07:04 / 16:47 | 07:12 / 17:02 | 06:54 / 16:58 |
| 15 Nov 2026 | 07:18 / 16:10 | 07:34 / 16:11 | 07:49 / 16:04 | 07:54 / 16:21 | 07:30 / 16:23 |
| 1 Dec 2026 | 07:44 / 15:54 | 08:02 / 15:53 | 08:19 / 15:43 | 08:22 / 16:02 | 07:56 / 16:06 |
| 21 Dec 2026 (shortest day) | 08:04 / 15:53 (7 h 49 min daylight) | 08:23 / 15:50 (7 h 28 min) | 08:42 / 15:39 (6 h 57 min) | 08:44 / 15:58 (7 h 14 min) | 08:16 / 16:05 (7 h 49 min) |
| 30 Dec 2026 (latest sunrise) | 08:06 | 08:25 | 08:44 | 08:46 | 08:18 |
| 15 Jan 2027 | 07:59 / 16:20 | 08:17 / 16:19 | 08:34 / 16:10 | 08:37 / 16:28 | 08:12 / 16:32 |
| 1 Feb 2027 | 07:39 / 16:49 | 07:54 / 16:50 | 08:08 / 16:45 | 08:13 / 17:01 | 07:51 / 17:01 |
| 1 Mar 2027 | 06:46 / 17:40 | 06:57 / 17:45 | 07:05 / 17:46 | 07:14 / 17:59 | 06:58 / 17:52 |
Times are sunrise / sunset; the 30 December row shows sunrise only, the latest of the winter. Glasgow is within a few minutes of Edinburgh, Newcastle between Manchester and Edinburgh; Inverness sees sunrise around 08:57 on 21 December.
What happens when the clocks go back on 25 October 2026?
British Summer Time ends at 2am on Sunday 25 October 2026. Overnight, sunrise in London moves from 07:40 to 06:41, so for a few weeks mornings feel lighter. The cost is paid in the afternoon: sunset in London moves from 17:48 to 16:46, and by 15 November it is before 16:25 in all five cities.
The lighter mornings do not last. By 15 November sunrise in London is back to 07:18, and by 1 December it is later than before the clocks changed.
Morning light is what nudges your body clock, the internal timer that runs your daily rhythm, earlier, so plan around your mornings rather than the early dusk. Light and your daily rhythm explains why.
When to start using a SAD lamp: month by month
- September. Sunrise is still before most alarms. Both DAYARC lamps are in stock in the UK and dispatched within 2 working days, so an order placed now is with you long before the darkest weeks.
- October. Sunrise in London passes 07:00 on 1 October and reaches 07:40 by the 24th; Edinburgh is at 08:02 by then. Many people notice the change this month and begin a morning routine: around 30 minutes with a lamp soon after waking on the days they get up in the dark.
- November. After the brief lift from the clock change, sunrise slides back past 07:30 in Manchester by mid-month and past 07:45 in Edinburgh. A good month to start if you have not; four months of dark mornings lie ahead.
- December. The shortest day is 21 December (7 h 49 min of daylight in London, 6 h 57 min in Edinburgh), but the latest sunrises come on 30 December: 08:06 in London, 08:44 in Edinburgh.
- January. Sunrise moves earlier only slowly: 07:59 in London on 15 January, 08:34 in Edinburgh. It is not too late to start; six or seven weeks of dark mornings remain.
- February. The turn. Sunrise is 07:39 in London on 1 February and 08:08 in Edinburgh, and it moves noticeably earlier each week. By the end of the month a 7am alarm in London or Cardiff goes off close to sunrise.
- March. Sunrise is 06:46 in London and 07:05 in Edinburgh on 1 March. Clocks go forward on Sunday 28 March 2027, moving sunrise an hour later on the clock for a while, but by then most people are waking in daylight. By late April, sunrise is before 6am across the UK.
When should you stop using a SAD lamp?
A common rule of thumb: keep going until you are regularly waking in daylight. For a 7am alarm that means around the start of March in London and Cardiff, and a little later in Edinburgh and Belfast. Some people taper over a couple of weeks; others carry on into spring because they get up very early or work indoors all day.
If a GP or other clinician suggested light therapy for seasonal affective disorder, follow their advice on when to stop rather than the calendar. We cover summer in should you use a light therapy lamp every day?
What if dark mornings feel like more than dark mornings?
Seasonal affective disorder (SAD) is a form of depression that comes and goes in a seasonal pattern, usually worse in winter. The NHS describes light therapy as using a bright light to simulate daylight, with 10,000 lux as the standard (lux is a measure of how much light reaches a surface). It also says light therapy is not usually available on the NHS because there is not enough evidence to tell whether it is effective, and lists talking therapies such as CBT and antidepressants as treatments.
If low mood is affecting your daily life, speak to your GP. If you have SAD, discuss the timing of any light routine with them rather than a sunrise table. Our post on winter blues vs SAD goes through the differences.
Frequently asked questions
When should I stop using my SAD lamp?
Once you are regularly waking in daylight: around the start of March in the south of the UK, a little later further north. If a clinician suggested light therapy, follow their advice.
Is it too late to start using a SAD lamp in January?
No. Sunrise in London is still 07:59 on 15 January and 08:34 in Edinburgh, and mornings stay dark for most early risers until late February.
Do I need a SAD lamp after the clocks go forward?
Usually not for the dark-morning reason. By 28 March 2027 sunrise is early enough for most people even after the hour is lost.
Does it matter where in the UK I live?
Yes, by up to about 40 minutes. On 21 December sunrise is 08:04 in London, 08:42 in Edinburgh, 08:44 in Belfast and around 08:57 in Inverness. The further north and west you are, the later the winter sunrise.
Where does this leave you?
If you get up at the same table every day, DAYARC Rise (£199) is the full-size lamp with four brightness settings and a 15, 30, 45 or 60-minute timer. If your mornings happen at a small desk or away from home, DAYARC Mini (£49.99) folds into its own cover. Whichever you choose, the calendar is the same: start when you are waking in the dark, and stop when you are not.
About DAYARC
DAYARC is a new UK circadian rhythm startup. We make two bright-light lamps for the morning: DAYARC Rise (£199), a full-size lamp rated at 10,000 lux at approximately 30–36 cm, with four brightness settings, a 15 to 60-minute timer and adjustable height and angle; and DAYARC Mini (£49.99), a compact lamp rated at 10,000 lux at approximately 25 cm, with a folding stand that doubles as its cover. Both use UV-free LEDs and run from the mains. We publish plain specifications with the measuring distance, we do not make medical claims, and we write the DAYARC Journal to help people build a simple morning light routine around their own daily rhythm. Both lamps are in stock in the UK and dispatched within 2 working days. You can read more about how we think on our approach page or compare the two lamps.
This article is general information, not medical advice. Check with a GP or qualified healthcare professional before using bright light if you have an eye condition, a condition affected by bright light such as bipolar disorder, or take medicines that increase sensitivity to light. If you have persistent low mood or think you may have depression, speak to your GP. If you or someone else is in crisis, call NHS 111 or, in an emergency, 999.