I'm not sure which category this would fall under. I live with my fiancé and have a son from a previous marriage. We are all three planning on moving to a bigger apartment, which is more expensive. I make a little bit more ( a couple of thousand) than my fiancé does a year. Previously, we had been splitting the rent 50/50 but decided that was unfair since a.) my son has his own room and is from a previous relationship and b.) I make more money than him. I am trying to figure out a "fair" way to split the rent when we move. Obviously, we wouldn't necessarily need a 2 bedroom if I didn't have my son so it seems unfair to make him pay 50/50. Please let me know if this belongs in another forum (such as family).

Thanks!

If this were me I would look at the price difference between a one and two bedroom apartment. Since your son is occupying that extra bedroom the associated extra cost should be your responsibility. You might want to look at a few different apartments and average the cost out to get a fair number.

jstrike makes a good suggestion. Another possibility is use sq footage. Take the total sq ft of the apt and divide that into the rent to get a cost per sq ft. Subtract the sq ft cost for the second bedroom and divide the remainder by half. Then add the sq ft for the second bedroom to your half.

I moved out of my apartment recently but me a guy I dated lived together and we split everything 50-50 also. I can see where you don't think it's fair for your fiancé to pay the same amount as you BUT, even though you have a baby, I think that should have been somehting he has considered already and that the financial responsibility of both of your lives should be shared equally, even if he isn't the little boys father... Do you see what I am saying? But if you disagree just take the rent and divide it by two then just add the difference of the two bedroom apartment to the one bedroom to your total... That's probably the easiest way to do it.

I think that should have been somehting he has considered already and that the financial responsibility of both of your lives should be shared equally, even if he isn't the little boys father.
Technically her son is not the financial responsibility of her fiancé... it's the father's. She may be receiving child support for her son which could be put towards living expenses. If she's not receiving support then it's up to her fiancé as to whether he wants to contribute financially towards her son. I would hope that he would be committed to both his future wife and her son and want to help out. He's going to be a role model for her son whether he realizes it or not. A new marriage with kids is tough enough, nit picking over finances only makes it worse.