My first thought was mural wallcovering. Instead of entire walls, something like this would trick the mind into looking out the window(s). While not this exact design, there are lots of options online.

Thank you Allison. I will definitely consider that.

Think jewel box instead!

I was looking for more of a bright rustic design idea. Since the room is so small with no natural lighting, I would rather no use darker colours as it will make the tiny room seem even smaller.

Thank you though.

Not sure if your budget would allow, but updated lighting and mirror will also help.

The accessories are what will draw the eye away from the feeling of it being so small.

I’d also suggest stencilling the floor.

How about something like this?

I was thinking along the same lines and since there is no storage the shelving ould also be useful . Not sure the resoning behind rustic but this might be the answer . Are you in NA or Europe?

I also agree different mirror and lighting.

I am not sure what you mean by rustic. But when I saw your little sink and the tangle of pipes beneath it, I recall making a sink skirt and attaching it around the front of my sink with Velcro tape. A natural wood shelf, some art, a wood framed mirror…might help. And some nice sconces on the side of your mirror for some light!

Some idea for wall decor

More bright light, light walls, less decor would make it visually large.

I love the idea of mural wallpaper, especially if it makes the room feel larger-like the pier photo Celery posted.

@ffpalms is that Susan Harter wall murals? I used them in our last house, powder room remodel. Didn't post earlier since the OP asked for rustic.

Get a small wall-mounted sink with a side faucet/wall mounted faucet so you don't have to have that cut-out for your current sink. If you like rustic, put in some beadboard wainscoting and paint it a bright white. I like the open shelf idea which you can add straw baskets to for storage. Here's what we did for a recent client. We had about the same dimensions, but a more rectangular configuration:

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Allison0704, your powder room is so gorgeous. To me, nature themes are rustic, especially with a wood countertop. I posted an image I found on Pinterest, so don’t know who makes that paper, but they are very similar. I love the sky detail in yours, and the soft blue of the distant hills. Thanks for posting it!

It will take very little wallpaper to do a tiny powder room. Find something rustic/lodge style that suits your own taste. Follow through with accessories.

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