It is spoken in the districts of Tupe and Catahuasi in Yauyos Province, Lima Region, Peru.

Kawki, a divergent dialect, is spoken in the nearby communities of Cachuy, Canchán, Caipán and Chavín by a few elderly individuals (9 surviving in early 2005).

Hardman[citation needed] has noted that while Jaqaru and Kawki share a degree of mutual intelligibility, speakers of one were unable to understand tape recordings of the other, and in a few cases of marriage between Kawki and Jaqaru speakers, the home language was Spanish.

Additionally, regressive vowel harmony is present throughout the verb person system in Jaqaru, but does not appear in Kawki.

Jaqaru contains six vowels- three of regular length and three short, whereas Kawki has only the three regular-length vowels.

Also characteristic of the Jaqaru morphology (and all of the Jaqi languages) is the use of extensive vowel dropping for grammatical marking.

One set involves the interplay of nouns with the rest of the sentence (there are 10 of these suffixes: 4 possessives, 5 directionals, and 1 object marker).

Nominal morphology is based on a four-person paradigm which marks the relationship of the second person to the utterance.

A great deal of the grammatical work of the language is done within the verbal morphological system.

The standard paradigm is of ten persons, which define the relationships between the four basic persons (Hardman, 2000, 56): In Jaqaru (and all other Jaqi languages), the tie between object and subject is one of union; they are not separable morphologically, and conjugation requires simultaneous specification of both as a unit.

Morphological words and syntactic phrases which do not contain a sentence suffix are judged by native speakers to be ungrammatical and for some, impossible to say (Hardman, 2000).

Classes II, III, and IV occur most frequently and are considered the core of syntactic inflection.

Four greetings are used in Jaqaru for addressing people, which mark the sex of the speaker and the addressee and do not carry any suffixes of any kind.

Four special particles take no suffixes and comprise utterances in and of themselves: Jira (“Let's go”), Jalli (“I don't know, could be.”), Wala (“Go on, get going, bye.”), and Chiku (“I'm going, I'm off, bye.”) (Hardman, 2000: 115).