Say it back
Original guidanceReply with Jumma Mubarak to you too, or Jumma Mubarak, same to you.
Reply guide
Short, polite replies to Jumma Mubarak, from a simple "to you too" to a dua, in English, Urdu and Arabic.
The simplest reply is Jumma Mubarak to you too. Add Jazakallahu khairan or a dua for a warmer answer.
Updated
What to say
Any kind reply is fine. These are the most common ones.
Reply with Jumma Mubarak to you too, or Jumma Mubarak, same to you.
Jazakallahu khairan means may Allah reward you with good. It suits a warm message with a dua.
Ameen is the usual reply to a dua. You can add: may Allah accept it from both of us.
آپ کو بھی جمعہ مبارک means Jumma Mubarak to you too. In Roman Urdu, Aap ko bhi Jumma Mubarak.
جمعة مباركة لك أيضا means a blessed Friday to you too.
Practical
Three quick checks.
Match the language of the message
Keep it as short as theirs
Add a dua if they sent one
Helpful answers
No reply is required, but a short kind answer is polite. Saying it back is enough.
Jumma Mubarak to you too is the simplest reply. Add Jazakallahu khairan or a dua for a warmer one.
Ameen means may it be so. It is said after a dua.
A reply does not need to be long. Say it back, add a dua if you like, and share the greeting forward.