Lisbon does two things at once. It is a capital city with a major airport and costs that stay low by Western European standards, and it is ringed within an hour by palaces, tiled quintas and Atlantic coastline. That combination gets you a European palace celebration without the Tuscan or French Riviera price tag. The food and wine are the other half of the argument, and they do more for a reception than any decor budget will.
Guests get a real trip out of it too. The city fills a long weekend on its own: the hilltop miradouros, custard tarts in Belém, fado in the Alfama, an afternoon on the coast. And because Lisbon is a major international hub, the travel day is far gentler than a remote island or a countryside estate hours from the nearest airport. Sintra, the region's most coveted wedding backdrop, sits roughly 30 minutes from Lisbon Airport inside a UNESCO World Heritage cultural landscape.
Then there is the infrastructure. Planners here speak English, venues have been running foreign weddings for years, and vendors handle international couples every weekend of the season. You are not pioneering anything. Whatever you are about to ask, someone in Lisbon has answered it before.