The short answers
What is the difference between authorised and unauthorised absence?
Authorised absence is absence the school has given permission for, or that the law accepts, such as illness (I), a medical appointment (M) or religious observance (R). Unauthorised absence is absence the school has not accepted, such as a holiday it did not grant (G), a late arrival after the register closed (U), or absence with no reason yet (N). Both count as absence in a pupil's attendance, and only unauthorised absence counts towards a penalty notice.
What does attendance code N mean?
N means the reason for absence has not yet been established. It counts as unauthorised absence. The correct code should be entered as soon as the reason is known, and no more than five school days after the session; if no reason can be established by then, the school must change it to O, absent in other or unknown circumstances.
Is a late mark an absence?
It depends when the pupil arrived. L, late before the register closed, counts as present. U, late after the register closed, counts as unauthorised absence for that session.
Does dual registration count as an absence?
No. D, dual registered at another school, is not a possible session at your school at all, so it counts neither for nor against the pupil's attendance. The other school records the session.
Present
The pupil is in school. A late arrival before the register closes counts as present. In the DfE's terms: counts as present.
| Code | What it means |
|---|---|
| / | Present in the morning |
| \ | Present in the afternoon |
| L | Late, arrived before the register closed |
Approved educational activity
The pupil is not in school but is taking part in supervised education the school has approved. It counts as present. In the DfE's terms: approved educational activity, counts as present.
| Code | What it means |
|---|---|
| B | Any other approved educational activity |
| K | Education provision arranged by the local authority |
| P | Supervised sporting activity |
| V | Educational visit or trip |
| W | Work experience |
Authorised absence
The school has given permission, or the reason is one the law accepts. It still counts as absence in the attendance figures. In the DfE's terms: authorised absence.
| Code | What it means |
|---|---|
| C | Leave of absence for exceptional circumstances |
| C1 | Leave of absence for a regulated performance or employment |
| C2 | Leave of absence on an agreed part-time timetable |
| E | Suspended or permanently excluded, no alternative provision |
| H | Authorised holiday, a code no longer in use |
| I | Illness, not a medical or dental appointment |
| J1 | Leave of absence for an interview |
| M | Medical or dental appointment |
| R | Religious observance |
| S | Study leave for a public examination |
| T | Parent travelling for occupational purposes |
Unauthorised absence
Absence the school has not accepted. It counts towards the ten sessions in ten school weeks at which a family is at risk of a penalty notice. In the DfE's terms: unauthorised absence, counts against attendance.
| Code | What it means |
|---|---|
| G | Holiday not granted by the school |
| N | Reason for absence not yet established |
| O | Absent in other or unknown circumstances |
| U | Late, arrived after the register closed |
Not a possible session
The session is not one the pupil could have attended, so it counts neither for nor against their attendance. In the DfE's terms: not counted in the attendance figures.
| Code | What it means |
|---|---|
| D | Dual registered at another school |
| Q | Unable to attend, lack of access arrangements |
| X | Not of compulsory school age, not required to attend |
| Y | Unable to attend, unavoidable cause |
| Z | Prospective pupil, not yet on the admission register |
| # | Planned whole-school closure |
| Y1 | Unable to attend, transport normally provided not available |
| Y2 | Unable to attend, widespread disruption to travel |
| Y3 | Unable to attend, part of the school premises closed |
| Y4 | Unable to attend, the whole school site unexpectedly closed |
| Y5 | Unable to attend, in criminal justice detention |
| Y6 | Unable to attend, in line with public health guidance or law |
| Y7 | Unable to attend, any other unavoidable cause |
What changed in the DfE's guidance
The codes to check in an older export
J is now J1, leave of absence for an interview, and counts as authorised absence rather than approved activity. D, dual registration, is not a possible session. K, education arranged by the local authority, and the Y1 to Y7 reasons for being unable to attend are newer codes. H, authorised holiday, is no longer in use; a session still coded H in an older export is read as authorised.
Where this comes from: Working together to improve school attendance, the DfE's statutory guidance, 2026 edition, which sets out each code and how it is classified for statistical purposes. See also the ten-week duty and school attendance national averages.
Every code, counted for you
adsum reads the codes in the exports your MIS already produces and counts each one the way the DfE does. It lists the N codes still waiting for a reason, shows which weekday or session a child tends to miss, and counts unauthorised sessions over the exact ten school weeks, so a family can be supported long before a fine is discussed.
Or ask us for a trial on your own school's data.