Where to fill up fresh water on the route?

Doing the NC500 in a campervan next month. Where can you fill up fresh water tanks along the route? Worried about running out in the remote sections.

Most campsites will let you fill up for a couple of quid even if you're not staying. Broomfield in Ullapool, Sango Sands in Durness, and Applecross campsite all have taps. Some petrol stations too.

The public toilets at Durness have an outdoor tap that's perfect for filling up. Also the ones at Bettyhill. Ask nicely at village halls too - most are happy to help.