Skolkoll's warning signals identify schools that deviate negatively from the national average on key metrics such as teacher certification, pupil-teacher ratio, SALSA results and absence. Of Sweden's 7507 active schools, 1684 have at least one warning signal — and 0 have three or more.
Important: A warning signal is not the same as a bad school. It is an indicator that there are data points that deserve closer examination. Skolkoll is a data aggregator — we present data and let the reader draw their own conclusions.
How warning signals work
We calculate four types of signals based on official statistics:
- Low teacher certification — the share of certified teachers is at least 1 standard deviation below the national average (774 schools)
- High pupil-teacher ratio — more pupils per teacher than the national average + 1 standard deviation (739 schools)
- SALSA underperformance — the merit score is at least 15 points lower than expected given pupil demographics (280 schools)
- High absence — more than 10% of pupils have over 20% unauthorised absence (0 schools)
National overview
Flagged schools
1684
of 7507 total
109 with 2+ signals
Red level
821
schools with serious deviations
0 with 3+ signals
Of the flagged schools, 1125 are municipal and 559 are independent.
Top 20 — schools with the most warning signals
| # | School | Municipality | Signals | Severity |
|---|---|---|---|---|
| 1 | Academy X Economy and Business Kristianstad | Kristianstad | 2 | Red |
| 2 | Anders-Olofskolan | Ragunda | 2 | Red |
| 3 | Arenaskolan grundskola | Timrå | 2 | Red |
| 4 | Björksätraskolan F-9 | Sandviken | 2 | Red |
| 5 | Brageskolan | Sollentuna | 2 | Red |
| 6 | Brönjaskolan | Boden | 2 | Red |
| 7 | Calmare Internationella Skola | Kalmar | 2 | Red |
| 8 | Cultura Gymnasium | Helsingborg | 2 | Red |
| 9 | Dalarö skola | Haninge | 2 | Red |
| 10 | Djurgårdsskolan 7-9 | Kristinehamn | 2 | Red |
| 11 | Drottning Blankas Gymnasieskola Sundsvall | Sundsvall | 2 | Red |
| 12 | Ekeby skola | Bjuv | 2 | Red |
| 13 | Entréskolan Västerås | Västerås | 2 | Red |
| 14 | Eriksdalskolan 2 | Skövde | 2 | Red |
| 15 | Ervalla skola | Örebro | 2 | Red |
| 16 | Fjällenskolan | Järfälla | 2 | Red |
| 17 | Fria Läroverken Norrköping | Norrköping | 2 | Red |
| 18 | Friskolan Vintergatan | Ljusdal | 2 | Red |
| 19 | Fritslaskolan | Mark | 2 | Red |
| 20 | Frösåkersskolan | Östhammar | 2 | Red |
The list shows the 20 schools with the most concurrent warning signals. Note that the signals are based on the most recent available statistics and individual schools may have taken action since the measurement period.
Municipalities with the highest share of flagged schools
| # | Municipality | Flagged schools | Share | Of which red |
|---|---|---|---|---|
| 1 | Älvdalen | 4 of 5 | 80% | 3 |
| 2 | Nykvarn | 3 of 5 | 60% | 0 |
| 3 | Haninge | 24 of 41 | 59% | 11 |
| 4 | Strömsund | 6 of 11 | 55% | 5 |
| 5 | Nacka | 30 of 59 | 51% | 22 |
| 6 | Österåker | 12 of 24 | 50% | 8 |
| 7 | Ragunda | 3 of 6 | 50% | 3 |
| 8 | Vansbro | 4 of 8 | 50% | 1 |
| 9 | Burlöv | 7 of 14 | 50% | 2 |
| 10 | Ånge | 5 of 10 | 50% | 2 |
| 11 | Övertorneå | 3 of 6 | 50% | 2 |
| 12 | Täby | 24 of 49 | 49% | 13 |
| 13 | Ludvika | 11 of 23 | 48% | 7 |
| 14 | Pajala | 5 of 11 | 45% | 3 |
| 15 | Upplands Väsby | 11 of 25 | 44% | 6 |
The municipality ranking shows municipalities where at least 3 schools have warning signals, sorted by share. Rural municipalities with few schools tend to rank higher — a single school can give a high share.
Conclusion
Warning signals are a tool for identifying schools that may need more attention, not a verdict. Most schools in Sweden have no flags at all. But for the 1684 that do — especially the 0 with three or more signals — there is reason to look more closely. Search for and explore individual schools in detail via the search page.
Cite this analysis
Skolkoll (2026). Warning signals 2026. skolkoll.se/en/analyses/varningssignaler-2026/. Retrieved 2026-04-13.