A sensitive subject

You should bring it up to him but only you will know the best way to bring it up without hurting his feelings since you know him better than any of us.

I agree that you should be able to just come out and say it. It's hard, I know, and it takes a long time to start getting comfortable saying anything like that. But, you're going to spend the rest of your lives together, and if you don't tell him, who will?

If you still don't want to be straightforward and say it, just pay with your phone on the couch and start snapping pictures of him (especially if you're sitting and he's standing, because then the angle will be unflattering and exaggerate it). Then cuddle up with him and check out his art. Chuckle at funny faces he made in the pictures, etc. Let him see for himself, without making a big deal of it.

...yes, I am sneaky, and only use these powers for good.

In the most tactful was possible I would point out his clothes are getting to small for him. He can buy bigger ones or lose weight his choice. When I started dating my boyfriend we both put on a lot of weight. One day I had enough and began eating healthy & exercising. After a while he wanted to have what I was eating because it looked good..sure I'll come for a run or do a Jillian dvd with you no point in sitting looking at you doing it. Next of all he is 50 pounds down. Gone from a XL to a M. Invite him along for walks/classes/gym etc. Offer to cook him the same thing you are eating. Good luck.

Oh and if that doesn't work just tell him De Nile isn't just a river in Egypt

This one's kinda hard, I mean I'm a dude and I'd hate to hear my girlfriend tell me to drop some weight. I noticed my weight gain through embarrassing pictures and now I'm working on getting rid of it. I'd say show him some recent pictures and ask him about joining a gym. I think if he notices your healthier lifestyle, he might want to mirror you and you can sorta be his inspiration to lose weight.

If you can't talk about this...you've got bigger problems than you know! I've had great results with starting out the conversation with...Your not going to like this conversation, but I just need 10 minutes of your time. Once it's out there...it's up to him!

You should try to make a joke out of it, so its not uncomfortable.

Guys can be amazingly sensitive about their weight gain and the size they wear. At my job we ordered safety vests for people who work in live traffic and the supplier was an asian company. The sizing was off by two sizes (i.e., a medium here would be an XL for this supplier). I thought the female employees would be upset, they were pretty understanding. One male employee, though, came storming into my office in a rage saying that he was a medium, not an XXL. Maybe he was a medium once, but he was certainly a large at the time. The vest fit him perfectly, but he still wanted a smaller size even after I patiently explained the size conversion issue. We gave him a new one and he was happy even though he looked like a safe sausage.

So tred carefully with your fiance. Alternate approaches and be patient--it make take some time to get through. Be direct, use humor, set a positive example in eating and exercising, invite him to join you, whatever you can think of. Try not to nag and pick your spots, but don't ever give up because ultimately you are saving his life and improving the quality of yours.

If you cook for him, cook more healthfully, with less fat and carbs, more protein. You don't have to tell him its healthy, just "trying something new." When you go do things together, make them more active, like mini-golf, walk museums, botanical gardens, etc. Also, is he tall? My HB is and he fits better in XLTall size than XL. Maybe he could get some Large Talls until he either loses the weight or accepts the XL size.