I suppose it will depend on the nature of the unpaid work, if your acting as a care giver then no, but if your practising as a qualified nurse they may accept it.
You'd need to clarify with the NMC what they will accept
I am currently practicing in a corporation as a company nurse for more than a year and have dabbled in clinic duties in the past. I also did a few months of volunteer work in a tertiary hospital. My question is, do the NMC consider experience as a company nurse as part of that '1 year experience' rule. Because technically, I'm still practicing as a qualified nurse, just not in a clinical setting. Thanks for the help.