I've been out with this girl a couple of times already, we're going out again soon and once more after that to a concert.
I couldn't buy the tickets online, so she did. I've been brought up in a way that man always pays for the woman, for all our dates I was the one who was paying, also she's a student and doesn't have much income.
How do I give her the money for the tickets in a polite way?
Note: We are from eastern europe.
In order to give her the money while avoiding to be seen as rude, you need to not assume what she wants.
If you assume that she wants you to pay her back and she, in fact, doesn't, you will put her in an uncomfortable position. You might hurt her feelings because she was happy to offer you those tickets but, now, you are treating it differently.
If you assume the other way around (she, in fact, doesn't want you to pay her back), the situation is still not great. You might put her in a difficult financial situation or she might resent you to have "trick her" into buying tickets for her.
To avoid both of those situations, I would suggest stating what you want and saying something like:
I feel bad for not buying those tickets and would like to pay you back. Is that okay with you?
First, you state how you feel. This way, when you tell her what you want to do (pay her back), she doesn't need to assume your reasons, she already knows. From experience, assuming someone reason and being wrong can lead to a lot of unnecessary conflict and resentment, so it's a good idea to try to avoid that.
Then, you check with her if she is okay with your solution (to solve the problem of you feeling bad). This way you show to her that it's not all about you and that her feelings also matters.
If she isn't okay with you paying her back, she can then say it and find another solution with you. If you didn't ask if she was okay with it, she might have not said anything because she didn't want to upset you but then resent you for not taking her feelings into account.
Note: I'm from France.
I'm not sure what is common in your culture, but in the Upper Midwestern U.S. I would fear that the existing answer to say you "feel bad" for not paying and then asking if you can pay is sort of inviting the other person to reassure you and deny the request (even if they'd prefer you pay). I don't know why we choose to communicate this backwards way, but we do. I think I am agreeing with @Spagirl's comment here.
Instead, from your question I am assuming that A) You intended to pay for the tickets all along, and B) Because of some technical difficulty or inconvenience, the other person did the actual step of making the purchase - I know I've been in this situation several times with friends especially when tickets are in demand or are otherwise a hassle to get. A tactful way would be to suggest/offer a way to pay them back, that way you don't set up a yes/no question on the topic of whether you will pay.
They can still step in and offer that you don't need to pay if they intend to keep the cost, but you've shifted the "status quo" to be in the area of you paying.
Some options: "Do you use (payment app) so I can send you money for the tickets?" "Do you mind if we stop at the cash machine so I can pay you back for the tickets?" etc.
