The timezone of Cuba
Timezones are always computed by their difference to UTC, the "Universal Time Coordinated". In Cuba exists only a single tonezone at UTC-5. E.g. Los Angeles has the Pacific Standard Time at UTC-8 and the time difference between LA and Cuba is 3 hours.
They have a nationwide clock change from standard time to daylight saving time, where the clocks are switched forward by 1 hour in summer.
The next clock change in Cuba will be on November 01st, 2020 at 1:00 to standard time. Back to overview: Cuba