Train from Copenhagen to Stockholm

By posting identical questions on the Denmark and Sweden Forums, you are likely to get identical answers on both. Keep your answers all in one place by deleting one of them.

You should definitely consider buying tickets ahead of time, as prices differ for different
departures.

Book directly on the Swedish rail site Swedish Rail, trainline, for example, does not
seem to have a relationship with Swedish Rail.

You will most likely have a connection somewhere along the way in a potentially small
city, so you need to keep track of where you are so you don't miss it.

https://www.seat61.com/international-trains/trains-from-Copenhagen.htm#Copenhagen-Stockholm

I will add that in addition to prices (which can be very high if you book too close to your travel at busy days/times), you may also find that long distance trains in Sweden regularly sell out closer to departure. In this sense, the Swedish railway market mimic the airline industry in terms of tickets, pricing and availability (but without the check-in, luggage restrictions, security, etc.).

So if you wait until the travel day, you risk paying a very high price and risk being very limited in your travel options if it is a busy day.

Buy the ticket from the operators themselves: SJ or Snälltåget.

I have been researching train transportation for both Sweden and Denmark this week as we leave for Stockholm on September 6th. I found that the Rome 2 Rio site had great options for the train from Lund (near Malmo, we have friends there we are spending 2 days visiting) to Aarhus in Denmark. I am sure you could find options there for your travel from Stockholm to Copenhagen. I will be using www.sj.se to book our tickets for Stockholm to Lund.

I used the www.sj.se site to book Lund to Stockholm many months ago for an upcoming September trip. I wanted a Night Train and they seem to sell out quickly. The sj site offered a higher price for a cancellable reservation, which I took because we were just beginning planning.