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

No. The gap stays at 5h all year.

When is the best time to call Moscow from Manila?

Between 14:00 and 17:00 in Manila, which is 09:00 to 12:00 in Moscow.

Manila is 5h ahead of Moscow. This gap is the same all year — neither city shifts its clocks relative to the other.

Manila

Philippines

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Moscow

Russia

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A 9-to-5 day in each city overlaps for 3h. That is 14:00–17:00 in Manila, which is 09:00–12:00 in Moscow.

City	Time zone	UTC offset
Manila · Philippines	Asia/Manila	UTC+8
Moscow · Russia	Europe/Moscow	UTC+3

What is the time difference between Manila and Moscow?: Manila is 5h ahead of Moscow. This gap is the same all year — neither city shifts its clocks relative to the other.
Does the time difference between Manila and Moscow change during the year?: No. The gap stays at 5h all year.
When is the best time to call Moscow from Manila?: Between 14:00 and 17:00 in Manila, which is 09:00 to 12:00 in Moscow.