Many different types of census schedule (census return or census form) are found in the 1921 Census of England & Wales.
Each schedule type is identified by a schedule type code (such as E or W) that can be found above the royal crest above the address panel on the front of the schedule.
The schedule type code may be repeated towards the foot of the page on the backs of schedule types which exceed two pages.
Continuation pages of the longest forms may receive an alpha suffix, as in, for example, IIIa as a continuation of the longest institutional schedule type.
The following schedule type codes are found in the 1921 Census of England & Wales. Note that the two types from Scotland (A and D) appear in the England & Wales Census by accident, the users having crossed the border between being given a Scottish census schedule and handing them in completed in England & Wales after census night.
| Schedule type code | Schedule type |
|---|---|
| A | Scotland household, single page, 10 entries |
| A | Channel Islands household, single page, 10 entries |
| AA | Channel Islands household, multiple page, 40 entries |
| AS | Channel Islands shipping, multiple page |
| C | Wales household, Welsh language, single page, 10 entries |
| CC | Wales household, Welsh language, multiple page, 40 entries |
| D | Scotland shipping, single page, 10 entries |
| E | England household, single page, 10 entries |
| EE | England household, multiple page, 40 entries |
| EEE | England household, multiple page, 70 entries |
| I | Institution, multiple page, 40 entries |
| II | Institution, multiple page, 70 entries |
| III | Institution, multiple page, 70+ entries |
| M | Isle of Man household, single page, 10 entries |
| MM | Isle of Man household, multiple page, 40 entries |
| MS | Isle of Man shipping, multiple page |
| NM | Armed Forces, multiple page, 70+ entries |
| P | Prison, multiple page, 40 entries |
| PP | Prison, multiple page, 70 entries |
| PPP | Prison, multiple page, 70+ entries |
| S | Shipping, single page, 10 entries |
| SS | Shipping, multiple page, 70 entries |
| W | Wales household, English language, single page, 10 entries |
| WW | Wales household, English language, multiple page, 40 entries |
| WWW | Wales household, English language, multiple page, 70 entries |