Njáls saga stands out among the Sagas of Icelanders (Íslendingasögur) in that an unusually high number of early manuscript witnesses are preserved. The saga is extant in around 60 manuscripts, 21 of which are parchment manuscripts from the period 1300-1600.
Despite the high number of parchment manuscripts, no single medieval witness preserves a complete text. All of these older manuscripts are fragmentary. Some of them amount to only a couple of leaves; six, however, may be said to contain the bulk of the saga:
The saga is generally believed to have been compiled around 1280 and there are 12 witnesses that date to the 14th century, i.e. 5 of the manuscripts listed above and 7 from the collection of fragments catalogued as AM 162 b fol.
- AM 162 b fol. β (beta), c. 1300
- AM 162 b fol. δ (delta), c. 1300
- AM 162 b fol. ζ (zeta), c. 1325
- AM 162 b fol. κ (kappa), c. 1350
- AM 162 b fol. γ (gamma), c. 1325
- AM 162 b fol. θ (theta), c. 1325
- AM 162 b fol. η (þeta), c. 1350
In the 17th century, there was one additional parchment codex still extant which was subsequently lost. This was called Gullskinna by Bishop Brynjólfur Sveinsson, and a number of 17th- and 18th-century paper copies of it are still extant.