Perth is 7 to 8 hours ahead of London, depending on the time of year. If you are both awake 7 am to 11 pm, a January weekday gives you 8 hours awake at the same time, though none of them is outside a 9-to-5 for both of you (in July: 9 hours shared, 0 hours free). Here are the good ones.
Perth is 8 hours ahead of London that week. On a weekday you are both awake for 8 hours, but none of them is outside work for both of you, so a lunch break or a commute has to do the work.
Worked out for the week of 11 January 2027 (11 Jan – 17 Jan), in London time, with each zone’s own daylight-saving rules for those dates. Perth awake 7 am – 11 pm, working 9 am – 5 pm weekdays; London awake 7 am – 11 pm, working 9 am – 5 pm weekdays.
A weekday, in London timeboth awake
Londonawake 7 am – 11 pm
Perthawake 7 am – 3 pm and 11 pm – 7 am London time
7a10a1p4p7p10p1a4a7a
Best on a weekday
noon – 2 pm London
8 – 10 pm Perth · London lunchtime, Perth evening · during London’s lunch break
Another weekday option
9 – 11 am London
5 – 7 pm Perth · London morning, Perth early evening · during London’s work hours
The long weekend call
Sat 10 am – 1 pm London
Sat 6 – 9 pm Perth · London morning, Perth early evening
The week · London time, 11 Jan – 17 Jan
7a
8a
9a
10a
11a
12p
1p
2p
3p
4p
5p
6p
7p
8p
9p
10p
Mon
3p
4p
5p
6p
7p
8p
9p
10p
11p
12a
1a
2a
3a
4a
5a
6a
Tue
3p
4p
5p
6p
7p
8p
9p
10p
11p
12a
1a
2a
3a
4a
5a
6a
Wed
3p
4p
5p
6p
7p
8p
9p
10p
11p
12a
1a
2a
3a
4a
5a
6a
Thu
3p
4p
5p
6p
7p
8p
9p
10p
11p
12a
1a
2a
3a
4a
5a
6a
Fri
3p
4p
5p
6p
7p
8p
9p
10p
11p
12a
1a
2a
3a
4a
5a
6a
Sat
3p
4p
5p
6p
7p
8p
9p
10p
11p
12a
1a
2a
3a
4a
5a
6a
Sun
3p
4p
5p
6p
7p
8p
9p
10p
11p
12a
1a
2a
3a
4a
5a
6a
Columns are London hours; the small figure in each cell is the time in Perth. both freeboth awake, one at workPerth asleep
The Perth–London gap through 2027
Dates
Difference
1 January – 27 March
Perth is 8 hours ahead of London
28 March – 30 October
Perth is 7 hours ahead of London
31 October – 31 December
Perth is 8 hours ahead of London
The week grid and call windows were worked out for 11 Jan to 17 Jan 2027 with the IANA time-zone rules for Australia/Perth (Perth) and Europe/London (London). That week London is on standard time and Perth keeps the same time all year. The table uses the same rules for every day of 2027. The finder above recalculates for the current week in your browser.
When it is … in London
In London
Perth, January
Perth, July
7 am
3 pm
2 pm
9 am
5 pm
4 pm
11 am
7 pm
6 pm
1 pm
9 pm
8 pm
3 pm
11 pm
10 pm
5 pm
1 am (next day)
midnight (next day)
7 pm
3 am (next day)
2 am (next day)
9 pm
5 am (next day)
4 am (next day)
Wednesday times. Send times as “your 8 pm” or “my 8 pm” so nobody has to guess whose clock you mean.
Stop doing the math every day
The Long Goodbye keeps your person’s local time and time of day on your home-screen widget and lock screen, so you can see whether it is morning coffee or midnight in Perth before you call. A “thinking of you” tap lights up their widget, and a countdown keeps the next visit in view.
What is the time difference between Perth and London?
Perth is 7 to 8 hours ahead of London, depending on the time of year. In 2027 it is 8 hours from 1 January to 27 March and from 31 October to 31 December; 7 hours from 28 March to 30 October.
What is the best time to call Perth from London?
In January, the easiest two hours on a weekday are noon – 2 pm London, which is 8 – 10 pm Perth: London lunchtime, Perth evening, during London’s lunch break. At the weekend, Sat 10 am – 1 pm London (Sat 6 – 9 pm Perth) gives you a longer call. Change the awake and work hours in the finder on this page to fit your own days.
How many waking hours do Perth and London share?
If both of you are awake from 7 am to 11 pm, you share 8 hours on a January weekday, but none of them falls outside 9-to-5 working hours in both places; in July it is 9 hours shared and 0 hours free.
Does daylight saving time change the call times?
Yes. In 2027 London changes its clocks on 28 March and 31 October and Perth does not change its clocks, so a call you keep at the same time in London moves by an hour in Perth on those dates. Check the table on this page and agree the new time out loud after each change.