Polaris introduced this four-seat RZR trail model for the 2019 model year as the RZR S4 1000 EPS, positioning it as a 60-inch-wide, recreational side-by-side aimed at tighter trail use rather than the broader, more aggressive XP family. It appeared in Polaris’s 2019 lineup as a new model and carried into 2020, where Polaris documentation continued to refer to the vehicle as the RZR S 1000 / S4 1000. The nameplate sat in the middle of Polaris’s RZR range, offering the brand’s familiar sport-side-by-side character in a package intended for families or groups who wanted four seats without moving up to a full-size general-purpose UTV.
For 2021, Polaris reorganized its trail lineup and replaced the S4 1000 naming with the RZR Trail S 1000 designation, which indicates that the exact RZR S4 1000 nameplate had a single continuous run from 2019 through 2020 and then was retired rather than revived later. As part of that era, the model became known as Polaris’s trail-focused four-seat RZR, bridging the gap between the two-seat trail machines and the larger four-seat performance models. Its significance is less about radical reinvention and more about giving the RZR family a dedicated compact four-seater for riders who wanted added passenger capacity while staying within a narrower trail-friendly footprint.