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

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

When is the best time to call Manila from Madrid?

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

Madrid is 6h behind Manila. This gap is not fixed: daylight saving time moves it between −7h and −6h during the year.

Madrid

Spain

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Manila

Philippines

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

City	Time zone	UTC offset
Madrid · Spain	Europe/Madrid	UTC+2
Manila · Philippines	Asia/Manila	UTC+8

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