Arlanda Express

They are easy to buy at the airport, but they are also easy buy in advance. So in the end it is a matter of personal preference and there is no right or wrong way.

I'm just thinking about possible flight delays so I'll just wait and buy at the airport. Is there signage in the airport that directs us to the train?
Thanks Badger

Yes, it's easy to find the train and to buy tickets. I've taken it a few times and just bought my tickets before boarding.

The tickets are not for a specific date or time:

• Valid for 1 one-way trip within 90 days

And are:

• Refundable until the last day of validity, activated tickets are non-refundable

https://www.arlandaexpress.com/summary

(Put a ticket in your cart to see these terms. )

So you needn't worry about flight delays.

As mentioned, a ticket bought in advance is not tied to a certain departure. Buying a ticket in advance means you can just board the next train to Stockholm when you arrive at the airport. It means you need to remember where the ticket is, but on the other hand it means that you don't have to worry about queues at the ticket machines. Although neither is in general a problem, so again, it's a matter of personal preference.

My two cents, I would buy the tickets online in advance. I personally find it easier on arrival in Europe jet lagged and addle brained to have one less thing to do/figure out. As a previous poster said, just don’t lose the ticket.

Thank you everyone.