The rolls' headings reflect the court's pattern of sittings. There were no terms, just a series of, on average, nine sessions a year at particular dates. In the fourteenth century at least these sessions seem normally to have lasted for two days. The dates of sessions from September 1441 to July 1485 have been worked out in detail, and show a regular pattern of 8 or 9 sessions per year. Until 1399 each roll covers the sessions held during a period of two or more years; there are no apparent gaps between 1304 and 1399.
Each roll consists of several separate rolls filed together. From 1399 to 1540, apart from the reign of Richard III, the rolls each cover a single year; only a single roll, for 4 Henry VII, seems to be missing for that period. The last of this sequence is made up of several constituent rolls covering 30 and 31 Henry VIII, eight sessions a year being held.
From October 1540 each roll is a separate sessional roll, two sessions only per year, one in the spring and one in the early autumn, being held, as prescribed by statute (32 Henry VIII, c 43; 33 Henry VIII, c 13; 34 & 35 Henry VIII, c 26). From that point the records are effectively those of the Court of Great Sessions, often later referred to as the 'assizes'. The pattern then established broadly continued (except for a brief sequence of rolls covering the two sessions of the year under Edward VI) until 1830, although within about 20 years the second session of the year came to be held in late summer, in August or September, rather than in October or November.
There was a gap in sessions of the court from 1643 to 1647, except for one session in 1644, because of the civil war, so that there is a gap in the series. A few sessional rolls are also missing for other years between 1540 and 1830, but in the early nineteenth century there are sometimes two and occasionally three rolls for a single session, and the series is in general remarkably complete. The sessions were virtually always held at Chester, but in 1716 they were held at Nantwich, because Chester castle was full of Jacobite prisoners.
The early rolls normally bear the name of the current justice at the head. Later, the rolls often have separate internal headings for gaol delivery, crown pleas and warrants of attorney, although there is a short sub-series of separate rolls of attorney, for various dates between 1343 and 1539. When there are no specific subheadings there is nevertheless a frequent tendency for some other distinct groups of entries (eg fines for licences to concord) to be grouped together.