Employment law on leave is largely uniform across England and Wales and Scotland, since the Employment Rights Act 1996 and the Equality Act 2010 apply across Great Britain, so a single discretionary unpaid leave form works in all three nations. The practical differences sit in the surrounding processes rather than in the entitlement itself. In Scotland, court and tribunal procedure differs, and employment tribunals operate under their own Scottish arrangements, so an employer defending an inconsistent refusal should take local procedural advice rather than assuming the English route applies identically.
Northern Ireland is the genuine outlier and deserves a careful note. Employment law there is devolved and does not run on the Employment Rights Act 1996; the equivalent provisions live in the Employment Rights (Northern Ireland) Order 1996, with its own time-off-for-dependants and parental leave rules administered through separate machinery. The substance is broadly similar, but the statutory citations, the enforcement body, and several procedural deadlines differ, so a template built strictly to the Great Britain framework should be checked against Northern Ireland provisions before it is relied on across the Irish Sea. If you employ staff in both jurisdictions, do not assume one form covers both without review.
Beyond the national borders, the only regional variation that bites in practice is internal. Larger employers often delegate leave decisions to local managers, and that is precisely where consistency breaks down. A request approved in one office and refused in another, for no recorded reason, is the textbook setup for a grievance. Documenting each decision on the same form, with the same fields, is what keeps a multi-site business defensible.