What is the cheapest way to travel between Lisbon and Porto?

Flixbus is the cheapest option if you book early — fares as low as €5–12 for the Lisbon–Porto route. Journey time is around 3.5–4 hours. Buses are comfortable with wifi and USB charging. Book at least a week ahead for the best prices; last minute can be €18+.

Rede Expressos is the Portuguese national bus company and usually charges €18–22. Slightly more reliable scheduling than Flixbus. Both depart from Sete Rios bus terminal in Lisbon, which is directly on the Blue metro line — very easy to reach.

The Alfa Pendular train takes just 2h45m and is the fastest option. Book early on CP's website for fares as low as €20–25. Last-minute prices hit €45+. The Intercidades regional train is slower (3h30m) but usually €18–22 even without advance booking.

BlaBlaCar is worth checking for carpooling. The Lisbon–Porto route has frequent drivers charging €8–15 per person. You're relying on a private driver so it requires flexibility, but it's often the best value and a great way to chat with locals.

Don't book CP train tickets at the station — you'll pay higher walk-up fares. Book on their website or app 30 days ahead when the cheapest seats release. Consider the CP Clube loyalty card if you're planning multiple rail journeys across Portugal.