Sertanejo is in 4/4 at moderate tempos (90-120 BPM) and is sung almost always in close two-voice harmony — the duets in parallel thirds and sixths that define the genre. Modern sertanejo universitário (the current commercial sound) uses electric guitar, accordion, bass, drum kit, and pop production; the older sertanejo de raiz ("roots" sertanejo) keeps the acoustic format of caipira folk (viola caipira, the ten-string Brazilian guitar tuned in five courses). Lyrics deal with rural life, love, infidelity, drinking, and small-town nostalgia; the modern version adds party themes and stadium choruses. Vocal phrasing is on the front of the beat, country-music style, with frequent use of cry-breaks and vibrato.

Sertanejo's roots are in caipira music from São Paulo, Minas Gerais, and Goiás — a rural folk form that the Cornélio Pires anthology recordings codified in 1929. The traditional duo format (two brothers in close harmony) crystallized in the 1940s-50s. From the 1970s, Chitãozinho & Xororó (active from 1970) and Leandro & Leonardo (1980s) moved the form toward pop production. Sertanejo universitário, beginning around 2006-08 with João Bosco & Vinícius and Jorge & Mateus, paired the duo format with pop-rock instrumentation and college-bar lyrics, and became Brazil's commercially dominant genre — by the late 2010s, sertanejo was the most-streamed genre on Spotify Brazil and the highest-grossing live circuit in the country, ahead of pagode and rock.

The two voices in parallel harmony are the signature — listen to how the upper voice usually a third above the lower one tracks every phrase. The accordion (sanfona) often plays a counter-melody in the instrumental breaks even in pop-production sertanejo. The kick-drum pattern in sertanejo universitário is straight 4/4 pop-rock; the older sertanejo de raiz uses a more loping caipira groove. Lyrics frequently include place names — small São Paulo and Goiás towns — and the names of romantic interests.

Jorge & Mateus's "Os Anjos Cantam" (2010) is a clean introduction to sertanejo universitário. For the older form, Tonico & Tinoco's recordings or Chitãozinho & Xororó's Cowboy de Aço (1986).

The Brazilian industry term "sertanejo universitário" — "university sertanejo" — was originally a marketing label invented around 2006-08 to position the genre toward middle-class college students who had previously rejected sertanejo as their parents' rural music; the label stuck and now denotes the dominant pop variant regardless of audience.