Can an employee convert their maternity leave to shared parental leave even if their partner does not take any shared parental leave?

Yes, provided that their partner meets the earnings and employment requirements, an employee can curtail their maternity leave and take shared parental leave instead. There is no requirement for their partner to take a period of shared parental leave.

An employee might choose to do this so that they can take leave in a more flexible way than would be possible if they remained on maternity leave. For example, they may want to take three separate periods of shared parental leave, interspersed with periods back at work.