How will you know if your husband is having an affair?

There are no set signs that mean your husband is having an affair but there are some red flags. If he is spending more time than usual away from home and his reasons are suspicious or can't be verified. If he's spending more money than normal on things that cannot be verified. If he's distant, if he changes his passwords on the computer/internet and doesn't tell you the new ones when he used to share them with you. Those are a few signs that I know of.

Well, he doesn't come home early and the salary he turned in is lacking. He always has a reason to come home late. Those maybe are some of the signs.

I'd be worried if he had a female friend about whom he was not toally honest. My husband and I both have friends of both genders, and we are totally honest with eachother. We are friends with eachother's friends as well as our own, so everyone knows everyone and can trust everyone.

Based on my experienced with my ex-bf, we don't need the sign. If we are so closed to him we will know or we will have that great instinct whether he's honest or instead of it. In my case although he that sweet mellow as always but I could feel something wrong somewhere. So if you guys out there who had sweet mellow partner, spouse, gf or bf, never ever think that they are that loyal. Still we have to check some where else to make sure we are not going cheated by our partner. I'm not saying this to terrify the others but at least be aware.