Sverige Taxi’s fixed rate between Arlanda Airport and the city center — and most likely to/from your hotel or ship, depending on where it is docked — is SEK450 (less than US$70 based on today’s exchange rate).
That’s cheaper than two going on Arlanda Express (although 2-for-1 rates are sometimes available on weekends, see the Arlanda Express website for more info). From the Arlanda Express terminal at Central Station, however, you’ll need to transfer by metro, bus or taxi if your hotel or ship is not within walking distance.
Taxi Stockholm is another good option, at SEK520 (about US$80), between the city center and airport.
We strongly recommend sticking with these two companies. Unscrupulous companies/drivers can rip you off in Stockholm, because taxis aren’t fully regulated. Taxi Stockholm’s posted fares for 10 kilometers, for example, are SEK295. However, we have seen fares as much as SEK1700 (ouch!) for the same 10 kilometers, which takes about 15 minutes in traffic.
When hailing a cab, look for the logos of Sverige Taxi or Taxi Stockholm for fair rates.