<prompt> Human: My girlfriend and I are moving in together after one year. I have been renting and she owns her condo, so we are obviously going to be sharing her place. We will be dividing all the bills down the middle heat, electricity, Internet, etc..., but we are trying to figure out a fair split on her mortgage and condo fees. Since she is benefitting by owning the place and building equity, we agree that I shouldnt pay quite as much, but what is a fair split? 4060? 4555?Edit: Just wanted to give a little extra info that I left out. My girlfriend and I make fairly similar wages, so in terms of income based payment percentage we wouldnt vary all that much. Also, she does currently have a roommate who is going to be moving out once I move in, so she isnt covering the the costs on her own. Thanks for all the responses. Its really appreciated.  <response>: Theres probably a dozen justifiable ways to split it. Most people will split based on income, which still opens up options proportional to income? Progressive like with US tax code?.Id probably feel okay if I were you or the GF if equity was subtracted out of the mortgage, and then 5050. You both benefit andor share equally from everything thats not principal: interest, taxes, insurance, and condo association benefits. 