Our bathroom door is too small for a walker or a wheelchair to fit in to get to toilet and he cannot walk. Suggestions?

If he has a walker, see if you can switch the wheels from "outside" of the walker's legs to "inside" of the legs. I had to do that with my mom's walker, and then she was able to get it through the doorway.

If you look at the wheels, there might be a little button, if you push that in, you should be able to remove the wheels, then find the corresponding holes along the inside of the legs, and line up the wheels with that.

How much too small?
It may be possible to widen the doorway, that may not cost as much as you think.
If it is only a couple of inches you could remove the door and hang a curtain, buy offset hinges, or hang a barn style sliding door.
Depending in his ability and your bathroom layout you may be able to strategically place grab bars and railings that would allow him to leave the walker outside the door.
Or as funkygrandma has suggested, a portable commode at bedside or wherever convenient may be the best option - buy as sturdy a one as you can find and afford.
And incontinence underwear is probably a good idea in case he can't get there in time.

You can use what is called a BEDSIDE COMMODE. They work great. If you cannot transfer him to that commode, and he can stand, then try to get what is called a "sit/stand" device. If he cannot stand... maybe his legs are too weak to stand then, you must keep him in bed and use a urinal for urine and bedpan for his bowel movements or.. put on diapers if bedbound. If he still doing some walking, can use pull ups but once he cannot walk, use those diapers... the kind that close using the tabs... like a baby diaper. Hope this helps you. GOD bless.

Probably time to start using a bedside commode then, along with a plastic urinal that you or he can hold on to while peeing at night. That is unless you want to pay a contractor to come out and widen the doorways. That can be quite costly. Best wishes.

I agree with advice below about a bedside commode and urinals. Safe and only requires a brief transfer. This site told me about commode liners and what a great help they are keeping the commode bucket(plastic) from absorbing odors. Much easier cleanup and you can buy from Walmart or Amazon.

Many people take the doors off of the bathroom, bedrooms, etc. in order to get these devices through their doors.

There are several size walkers available. My mother in laws walker won’t fit thru the door either. I was at a friends home, same model home as mine. She just had knee replacement she has a walker that looks just like my mother in laws but is actually narrower. I will be getting it for my mother in law.

My Mom had to turn sideways to get into her bathroom. The toilet was right behind her when she finally got in. I couldn't widen the door because of the construction of my house.

A commode is a good idea. Maybe a screen to make it more private.

i use a Hoyer Lift with a sling that has an opening for her to go to the bathroom. I put disposable chucks and thick washable pads underneath her (on top of her hospital bed). It sounds weird but works really well and we’ve got the system down pat. This way she doesn’t have to soil herself in a diaper, and she is seated comfortably the same way she would be on a toilet.

I'm not sure where I would start with the looking, but have heard this come up before. Airlines have aisle chairs that are manufactured for the narrow aisles and maybe there are used ones? Of course the other options are the commode chair that can be placed in any room, or finding someone to do the modest home modification to enlarge that doorway...which will probably necessitate a new door or modification if possible of the old so that it shuts, or a curtain at least for the time being. I'd check with your local city hall for referrals, the building dept etc. or posting on Next Door what you are in need of.