The first is better, due to plumbing for the tub/shower. This is referred to here ( US) as your classic 5 x 8 bath. Plan a 21 d x 30 to 36 w inch ( 76 cm - 91) cm wall mount vanity/basin surround depending tub width, and don't run the top from entry wall to tub as you seem to have drawn?

Basically you have a bit of a fight with tub plumbing and door swing....the second allows much easier entry if the loo is "in use" but you're leaning around/over a toilet to get to tub water : ) Maybe a pocket door with the first plan.for the most optimal.

Then do the second layout, and move the tub plumbing to the opposite wall. It's pretty obvious the toilet locale in the first is a knee knocker if someone opens a door while it's in use. Yes? All 5 x8 baths are a space challenge, but a sink obviously requires less depth than a toilet. So do the second, and move the "water" in the tub. To the opposite wall : )

If you are bathing multiple small children , the FIRST will give you most tub access, with a move of tub plumbing to opposite wall........AND a pocket door. Depends who is using the bath.

My daughter's bathroom is like #2 (which is also what I've most commonly seen in the US). Honestly, the toilet makes a convenient seat while keeping a kid company during a bath, and I've never had any problem stepping next to the toilet to turn on the water (in her bathroom or ours) -- prefer to have the "entry" end away from the toilet, and that's the end far from the showerhead for most folks.

Also, it's nice to have the sink closest to the door not only for door swing, but because there are plenty of times when you step into a bathroom just to wash your hands, and it's nice not to have to walk around the toilet to do that. It's why I've always presumed that this layout was so common (along with plumbing considerations).

As for the basin, I suggest visiting a bath shop and looking at sinks in person. A large sink can be useful for, say, hand laundry or washing a baby, but a smaller sink can work just fine for 90% of what you use a bathroom sink for, so how to balance sink and counter space is mostly personal taste. In a small bathroom, the counter space might be critical.

Picture #2 is the typical and most common layout. Never seen a bathroom with a #1 layout. You want to have a vanity first when you walk into the bathroom and the toilet hidden more or less between the vanity and the tub.

We have #2 for one of the bathrooms. It seems to be best layout..you don't want 'hit' the toilet as you enter the bathroom..unless you don't have a lock on the door and want to block the door:)

Here is one of my favorite small bathrooms from houzz

#2 all the way

As I stated......... I have NO problem with the toilet next to the tub. Provided the TUB faucet goes to the wall : ) A far easier reach in, and logical roomier step out. If the plumbing for that were unable to move for whatever reason, and it was not mentioned unti later that moving it was no issue,......? "Inconvenient" becomes the word. unless tub plumbing is on an opposite wall from toilet soil pipe.

it's honestly not at all inconvenient. I never think about it.

(would be different with a rigid shower wall, but that's not really about toilet placement)

Do you bathe babies acm? I have a 5 x 8 , as the second layout, WITH plumbing for tub on the opposite wall from toilet soil pipe, and can not imagine lining those up on the same wall. And I HAVE no babies or small kids : ) I can't even imagine the pain of cleaning as ALL 5 x 8 baths are not particularly roomy lol.

To my mind, it's also a safety issue. We tend to exit the tub nearest the water, tubs get grimier nearest the drain . Give a soul some room.

Agree with greenfish, Jan -- you keep the babies at the far end from the faucets, so on the side away from the toilet. Also, I'm with those who like to get in on the end of the shower with no water and then walk into the spray. (Spouse even more so, as the water often isn't hot yet when he ventures in!)

For that matter, kid and I wash out a disassembled rodent cage every two weeks in this tub! Again, nice that we're kneeling away from the spray and can reach over for rinsing... And don't even ask me how much time I've spent either (a) sitting on the toilet to read to child in tub, or (b) sitting on the tub to read to child on toilet. oy!! :)

Of these, I prefer option 2, fro the reasons stated by others above.

You do have other options which separate the vanity and toilet some more if you wish, though with some more complicated plumbing

I've lived in houses with both layouts. I prefer the 2nd layout - especially if you have small children to bathe! Much easier to sit on the lid of the toilet than it is to kneel on the floor! Also only having one side of a vanity cabinet to clean is a win-win!