Its in title, but i think its an interesting question.

Everyone has their own ideas on that.
For most people like me (atheist), it's about how religious they are..
Spiritual is cool, but someone devoted to an organized religion is just going to end one way or another. Been there, done that. Tried to avoid the topic like an elephant in the room, but it's always there and no matter how much you like someone and try not to address it.... No one will change the others mind, and it's an important topic for both parties... So in a nutshell... If they're a part of an "organized" religion.. NO.

I agree with the last post. It is rather interesting that when I think back, everyone I have ever had any kind of romantic relationship with was similar to me as far as their beliefs are concerned.I suppose there is apart of me that can not tolerate anything else, which really narrows the window.

Religious people I can live with so long as they aren't pushy about their religion, or the type that thinks everything in the world has to reference god or jesus in some way. I just can't take it seriously, I'm an adult, I stopped believing in santa clause at age 11, how in the hell are their still people in their 50s-60s-70s .etc that still believe in a magic man in the sky, grow up I say.

I could never date a religious person as anyone who could believe in that stuff must be a total idiot or just plain ignorant.

I once dated a girl that was super catholic and we never had any issues when it came to religion. I'm ok with it as long as they don't try to push it on me.

I'm a deist leaning agnostic. As long as she knows and accepts that, sure, I would date her. I used to be married to one. I probably wouldn't be able to get along with a real holy roller or Bible thumper though. Or maybe she wouldn't be able to get along with me.

I could never date a religious person. Ever.

Its okay for me to date with a religious partner. I believe that differences are a must in between humans and that makes our life more enjoyous. If all are alike, I would say its not good. I am ready to adjust with my partner, but adjustment does not mean I will go to prayer meeting with my partner.

I can date a religious person. I have in the past, my thoughts are keep you opinion to yourself. I don't push being atheist onto u, do not do it to me. My problem would usually their family. In the past I would hide it, but then I'm not true to myself. So if u can't accept me because ur family has issues, then we need to part.

I've tried in the past, but it is really difficult. Therefore, I now only look for women who identify as atheist or agnostic so that there are no serious complications due to our beliefs.

I could, providing they weren't the obsessive type. If it's simply that they have beliefs that happen to differ from mine, but weren't all crazy about forcing me to follow that doctrine, then I'd be OK with it.

My brother's atheist and his girlfriend's Roman Catholic. She accepts it's not his thing and they pretty much just go about their business separately when it comes to faith. She goes to church, he doesn't. I don't even know if he plans on going to their daughter's Christening, though he isn't against her being Christened.

I've previously been with a guy who called himself a Scientologist, though he wasn't a practising one, so it never bothered me.

It can definitely make things difficult in the long term especially when children are involved. I'm going through a divorce and I told my wife I was atheist before dating. I believe it's best to have as much in common as possible with a partner there won't be a problem finding differences down the road. Compromise will be a necessity but don't compromise your soul. Lol. It's my belief most Christians are to afraid to admit or in denial of being agnostic. I asked myself long ago am I bad because I don't believe?

If he is a liberal i think that would be ok.

I wouldn't mind them being religious as long as they don't mind me being agnostic.

not at all , i can't stand someone who is talking about god or religion with every single breath ....

No, their warped sense of thinking really makes any conversation anything but pleasant.

It depends how open-minded, intellectually honest and smart this person is.
Based on my personal experience, I came to the conclusion that there are stupid and smart religious people as there are stupid and smart atheists/agnostics.
So I don't discriminate.
Religious people might have their own good reasons to believe in something, and I accept it. It's their right.
But as it is impossible to convert me (I cannot accept an idea that is not supported by very strong scientific evidence and just believe in it)the imaginary religious man I would date must accept my way of thinking.
I care much more about a man's intelligence, sensibility, honesty and education than his personal religious beliefs.

Even though I'm an atheist, I love a woman with strong faith of her own. There's an important difference between having faith and being religious; I like the former, but I've never been impressed by the latter. Having faith is a good indication that the female/person has values, standards, loyalty, and can stick to their word. It's... I don't know what the word is, "refreshing"? - to find someone who actually has beliefs and faith in something, as opposed to lip-syncing any religion. I think a lot of titles like "Catholic", "Christian", "Buddhist", etc, etc, get used improperly.

You can't really change them and there will be huge problems . Someone ends up saying something stupid and you find the need to carve your own brain out with a spoon for being dumb enough to have positive expectations from the delusional. I have no problems interacting with the moderately religious but when it comes to relationships it's just too much of a compromise .
If necessary you can make them watch "inherit the wind" and similar material for a few months before you take the plunge .
Or pretend to be religious and consider it a social experiment.