Does the time difference between Manila and Stockholm change during the year?

Yes. Because of daylight saving time the gap moves between +6h and +7h.

When is the best time to call Stockholm from Manila?

Between 15:00 and 17:00 in Manila, which is 09:00 to 11:00 in Stockholm.

Manila is 6h ahead of Stockholm. This gap is not fixed: daylight saving time moves it between +6h and +7h during the year.

Manila

Philippines

--:--:--

Stockholm

Sweden

--:--:--

A 9-to-5 day in each city overlaps for 2h. That is 15:00–17:00 in Manila, which is 09:00–11:00 in Stockholm.

City	Time zone	UTC offset
Manila · Philippines	Asia/Manila	UTC+8
Stockholm · Sweden	Europe/Stockholm	UTC+2

What is the time difference between Manila and Stockholm?: Manila is 6h ahead of Stockholm. This gap is not fixed: daylight saving time moves it between +6h and +7h during the year.
Does the time difference between Manila and Stockholm change during the year?: Yes. Because of daylight saving time the gap moves between +6h and +7h.
When is the best time to call Stockholm from Manila?: Between 15:00 and 17:00 in Manila, which is 09:00 to 11:00 in Stockholm.