Tell it how many queue days you have today and which areas you'd take. It adds a day per day from now on, and watches for an SSSB place whose queue-day requirement has dropped to meet your count.
You have to leave this page open — in a pinned or background tab is fine. There's no server behind this site, so a running copy of the page is the only thing that can notice a new listing. Close it and the watch stops.
A match arrives as a browser notification, so your browser will ask permission once. Your settings live in this page's address — bookmark it after you switch the watch on and you can pick the same watch up later, or on your phone.
SSSB only: Bostadsförmedlingen ads are decided by a deadline rather than a queue-day figure, so there's nothing for your running count to be measured against.
All available listings
1 SSSB queue
Register at sssb.se. You collect one queue day per day, and listings go to whoever applies with the most queue days — that's the number this dashboard sorts by.
To actually sign a contract you need to be a member of an SSCO-affiliated student union (or if you aren't registered for classes, an admissions letter works as well) and meet their study-pace requirements — check their current rules on the site.
Do this first: registering is quick and days only start counting from when you register, so every week earlier is a week higher in every future queue. You can collect a maximum of 90 days before registering with a student union (class registration required).
2 Bostadsförmedlingen
This is Stockholm's city housing agency — Svenska Bostäder doesn't run its own student queue, their listings are advertised here. Register at bostad.stockholm.se; there's a yearly queue fee, and offers go by queue time.
Student listings here often have much shorter effective queues than regular apartments — and unlike SSSB there's no student-union requirement to register, though student listings require you to be studying when you sign.
Note: ads here show an application deadline ("sista ansökningsdag") rather than a required queue-days figure — you apply and the longest-queued applicant wins, so it costs nothing to try even with few days.
Strategy
Join both queues ASAP, long before moving — they're independent and both reward early registration. Use SSSB queue days for the areas closest to most university areas (Lappkärrsberget, Jerum, Kungshamra are the classic first-year picks), and treat Bostadsförmedlingen as a good backup plan, as on average those offers are more expensive.