The most widely used classification is an alphanumeric coding system developed by Malcolm Guthrie in his 1948 classification of the Bantu languages.
It is mainly geographic.
The term 'narrow Bantu' was coined by the Benue–Congo Working Group to distinguish Bantu as recognized by Guthrie, from the Bantoid languages not recognized as Bantu by Guthrie.

In recent times, the distinctiveness of Narrow Bantu as opposed to the other Southern Bantoid languages has been called into doubt (cf.
Piron 1995, Williamson & Blench 2000, Blench 2011), but the term is still widely used.

There is no true genealogical classification of the (Narrow) Bantu languages.
Until recently most attempted classifications only considered languages that happen to fall within traditional Narrow Bantu, but there seems to be a continuum with the related languages of South Bantoid.

At a broader level, the family is commonly split in two depending on the reflexes of proto-Bantu tone patterns:  Many Bantuists group together parts of zones A through D (the extent depending on the author) as Northwest Bantu or Forest Bantu, and the remainder as Central Bantu or Savanna Bantu.
The two groups have been described as having mirror-image tone systems: where Northwest Bantu has a high tone in a cognate, Central Bantu languages generally have a low tone, and vice versa.

Northwest Bantu is more divergent internally than Central Bantu, and perhaps less conservative due to contact with non-Bantu Niger–Congo languages; Central Bantu is likely the innovative line cladistically.
Northwest Bantu is clearly not a coherent family, but even for Central Bantu the evidence is lexical, with little evidence that it is a historically valid group.

Another attempt at a detailed genetic classification to replace the Guthrie system is the 1999 "Tervuren" proposal of Bastin, Coupez, and Mann.
However, it relies on lexicostatistics, which, because of its reliance on overall similarity rather than shared innovations, may predict spurious groups of conservative languages that are not closely related.
Meanwhile, Ethnologue has added languages to the Guthrie classification which Guthrie overlooked, while removing the Mbam languages (much of zone A), and shifting some languages between groups (much of zones D and E to a new zone J, for example, and part of zone L to K, and part of M to F) in an apparent effort at a semi-genetic, or at least semi-areal, classification.
This has been criticized for sowing confusion in one of the few unambiguous ways to distinguish Bantu languages.
Nurse & Philippson (2006) evaluate many proposals for low-level groups of Bantu languages, but the result is not a complete portrayal of the family.
Glottolog has incorporated many of these into their classification.

The languages that share Dahl's law may also form a valid group, Northeast Bantu.
The infobox at right lists these together with various low-level groups that are fairly uncontroversial, though they continue to be revised.
The development of a rigorous genealogical classification of many branches of Niger–Congo, not just Bantu, is hampered by insufficient data.

Computational phylogenetic analyses of Bantu include Currie et al. (
2013), Grollemund et al. (
2015), Rexova et al.
2006, Holden et al.,
2016, and Whiteley et al.
2018.
The most widely used classification is an alphanumeric coding system developed by Malcolm Guthrie in his 1948 classification of the Bantu languages. It is mainly geographic. The term 'narrow Bantu' was coined by the Benue–Congo Working Group to distinguish Bantu as recognized by Guthrie, from the Bantoid languages not recognized as Bantu by Guthrie.
In recent times, the distinctiveness of Narrow Bantu as opposed to the other Southern Bantoid languages has been called into doubt (cf. Piron 1995, Williamson & Blench 2000, Blench 2011), but the term is still widely used.
There is no true genealogical classification of the (Narrow) Bantu languages. Until recently most attempted classifications only considered languages that happen to fall within traditional Narrow Bantu, but there seems to be a continuum with the related languages of South Bantoid.
At a broader level, the family is commonly split in two depending on the reflexes of proto-Bantu tone patterns:  Many Bantuists group together parts of zones A through D (the extent depending on the author) as Northwest Bantu or Forest Bantu, and the remainder as Central Bantu or Savanna Bantu. The two groups have been described as having mirror-image tone systems: where Northwest Bantu has a high tone in a cognate, Central Bantu languages generally have a low tone, and vice versa.
Northwest Bantu is more divergent internally than Central Bantu, and perhaps less conservative due to contact with non-Bantu Niger–Congo languages; Central Bantu is likely the innovative line cladistically. Northwest Bantu is clearly not a coherent family, but even for Central Bantu the evidence is lexical, with little evidence that it is a historically valid group.
Another attempt at a detailed genetic classification to replace the Guthrie system is the 1999 "Tervuren" proposal of Bastin, Coupez, and Mann. However, it relies on lexicostatistics, which, because of its reliance on overall similarity rather than shared innovations, may predict spurious groups of conservative languages that are not closely related. Meanwhile, Ethnologue has added languages to the Guthrie classification which Guthrie overlooked, while removing the Mbam languages (much of zone A), and shifting some languages between groups (much of zones D and E to a new zone J, for example, and part of zone L to K, and part of M to F) in an apparent effort at a semi-genetic, or at least semi-areal, classification. This has been criticized for sowing confusion in one of the few unambiguous ways to distinguish Bantu languages. Nurse & Philippson (2006) evaluate many proposals for low-level groups of Bantu languages, but the result is not a complete portrayal of the family. Glottolog has incorporated many of these into their classification.
The languages that share Dahl's law may also form a valid group, Northeast Bantu. The infobox at right lists these together with various low-level groups that are fairly uncontroversial, though they continue to be revised. The development of a rigorous genealogical classification of many branches of Niger–Congo, not just Bantu, is hampered by insufficient data.
Computational phylogenetic analyses of Bantu include Currie et al. (2013), Grollemund et al. (2015), Rexova et al. 2006, Holden et al., 2016, and Whiteley et al. 2018.
Bantu languages