Can I buy a travel class upgrade at the airport?

Yes, if there's availability. You can pay for the upgrade with money. At Helsinki Airport, Finnair Plus members can also use Avios or upgrade benefits.

Each Finnair Plus member must use their own Avios or upgrade benefits for the upgrade. You can't use your Avios or upgrade benefits to upgrade another member's travel class.

Please note that airport upgrades include fewer benefits than upgrades bought in advance through Finnair.com, the Finnair app or customer service. For example, priority services and lounge access aren't included in Business Class upgrades bought at the airport.