My husband owned his own home for about 3 and a half years prior to us getting married. After we got married I moved in and we sold the house after I had been living there just under two years. We moved in with my parents for 6 months while our new home was being built. During this time, we were able to live rent and utility free and saved some money to put toward the new house.
His home had been bought for about $160K and sold for $295K. That money, along with savings was used to purchase our new home. Four years into living at our new home we decided to divorce. That home was sold and we split the money equally between both of us. Now, while trying to finalize our divorce, he is telling me I owe him the money he had made on his previous home. Am I responsible for that money or did it become comingeled assets in our marriage?
We never had a prenuptial agreement and I did not work during our marriage due to raising our children.

What State? I'm in NY. I owned a house in my own name when I married my "ex." "We" sold that house and put the proceeds into our first joint house. When we divorced I was awarded all of what I turned over from house #1 toward house #2 and then we split the balance.

Again - this was in NY.

Some states (California for example) allow a reimbursement to a spouse for a separate property contribution to the acquisition of a community asset. So in your case for example, in California, your husband is correct. He would be entitled to be reimbursed from you for the money he invested in the house you bought together that he got from the sale of his other house (the one he had before marriage).

Also, the reimbursement is off the top so you do it like this: total net proceeds from sale of house minus his contribution from the sale of his other house reimbursed to him and then divide the remaining funds 50-50.

There may actually be more than that that he owes you because you presumably paid down the principle on his mortgage during the first two years of your marriage when you lived in his house, but that adds a layer of complexity you may not need to get into and it may be a small amount of money he'd owe you anyway.