I think it comes down to A) how religious the other person is, B) how religious you are, and C) how much you want to avoid potentially insulting the person.
If they are very religious and you are not, and you want to avoid any hint of insult to their religion or any potential conflict, better just say something religious or at least agreeing back: "
Thanks, same to you".
If you can't stand to say something that even acknowledges their beliefs, I think it at least doesn't hurt to acknowledge their sentiment, so you could just say "Thanks, bye.
" That's probably what I'd do.
english.stackexchange.com/users/380/Mr. Shiny and New 安宇
I had a friend in college who liked to respond to "God bless" with "Goddess protect".
As I recall he did so just to be different from us other geeks who would sometimes respond with "Live long and prosper".
Seriously, though, I think that a polite "Thank you" should be sufficient.
english.stackexchange.com/users/457/Ants
I'll often reply, "Take care."
Sounds a little warmer than "bye," and not particularly religious.
english.stackexchange.com/users/67/moioci
You could respond with a Jewish farewell, illustrating that not everyone sees the world the same way, but also probably alienating your friend Shalom!
Or you could be polite and simply say you too!
english.stackexchange.com/users/588/Ed Guiness
"Be well," said with a smile.
english.stackexchange.com/users/928/In the Booley House
The origin of "goodbye" (hence "bye") is "God be with you", so it is about on the same level.
I think "goodbye" (or perhaps "goodbye to you, too") could be appropriate, just "bye" perhaps not so much.
english.stackexchange.com/users/21/Peter Eisentraut
What should the correct response be (from someone not overtly religious) if someone says "God bless" when parting company?  "Bye now" or "Bye" doesn't seem an adequate response.
Response to "God Bless" when parting company
english.stackexchange.com
<politeness>
english.stackexchange.com/questions/2665
english.stackexchange.com/users/984/kguest
When parting company, there are many ways to respond to "god bless" and all will depend on how relgious you and the other person are. However, in most circumstances you could respond with "Take care" or "Thank you" or even simply "Goodbye". It depends on the context - if you want to avoid potentially insulting the person, a neutral option might be to say "Thanks, bye"
When parting company, there are many ways to respond to "god bless" and all will depend on how relgious you and the other person are. However, in most circumstances you could respond with "Take care" or "Thank you" or even simply "Goodbye". It comes down to A) how religious the other person is, B) how religious you are, and C) how much you want to avoid potentially insulting the person.  If they are very religious and you are not, and you want to avoid any hint of insult to their religion or any potential conflict, better just say something religious or at least agreeing back. If you can't stand to say something that even acknowledges their beliefs, I think it at least doesn't hurt to acknowledge their sentiment, so you could just say "Thanks, bye". The origin of "goodbye" (hence "bye") is "God be with you", so it is about on the same level, so "goodbye" (or perhaps "goodbye to you, too") could be appropriate, just "bye" perhaps not so much.
"Take care"; "goodbye"; or perhaps "goodbye to you, too" could be appropriate. The answer to this question will depend on how religious you are, how religious the other person is and how likely you are to offend them. However, there are a range of options to respond to "God bless", such as "Take care", "Thank you" or "Goodbye".
It comes down to A) how religious the other person is, B) how religious you are, and C) how much you want to avoid potentially insulting the person. A neutral option might be to say "Thanks, bye" You could try a jokey response like "Goddess protect" Another option is "take care" - warmer than "bye" and not too religious. You could use a Jewish farewell like Shalom or just say "you too" The origin of "goodbye" (hence "bye") is "God be with you", so it is about on the same level.  
It comes down to A) how religious the other person is, B) how religious you are, and C) how much you want to avoid potentially insulting the person.  If they are very religious and you are not, and you want to avoid any hint of insult to their religion or any potential conflict, better just say something religious or at least agreeing back. If you can't stand to say something that even acknowledges their beliefs, I think it at least doesn't hurt to acknowledge their sentiment, so you could just say "Thanks, bye" The origin of "goodbye" (hence "bye") is "God be with you", so it is about on the same level, so "goodbye" (or perhaps "goodbye to you, too") could be appropriate, just "bye" perhaps not so much.
The answer to this question will depend on how religious you are, how religious the other person is and how likely you are to offend them. There are a range of options to respond to "God bless", such as "Take care", "Thank you" or "Goodbye".