Jummah prayer time in Dammam is 12:06 PM. Time is same in all mosques of Dammam for Jummah Prayer. This time is aligned with Duhr prayer We can say that on Friday all the Mosques Pray Jummah Salah instead of duhr.
It is a rule in all over Saudi Arabia that prayer time is exactly after 20 minutes of Azaan. So If you are living any where in KSA you can go for Jummah Prayer onsame time as Duhr.
There are 2 faraz Rakats in this prayer and 4+4 Sunnah Rakats 2 Nawafil Rakats so total 12.
Usually people comes special and in big numbers to offer Jummah Prayer in Dammam so it is a good practice to go before the time as soon as possible and keep a clean cloth because may be you cannot find a clean place due to rush.

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