I admit to not being a big beach buff but Montserrat does have a few great beaches to enjoy.
Lime Kiln Beach is worth the trek to get there. Quite secluded and a true spot to get away and relax.
Rendezvous Bay is the called the only white sand beach on island but I don’t think the sand looks all that white at times. You can also only get to Rendezvous by boat or hiking.
Bunkum Bay is quite secluded. So much so I’ve never been to it.
Isles Bay and Old Road Bay are also nice choices.
Woodlands Beach has had a makeover in the past few years from the Montserrat Tourist Board. So there is a nice covered picnic area, refurbished showers and changing rooms.