In Mexico, conservation agriculture has been mainly implemented using permanent beds, where the top of the raised beds is not tilled, which allows them to obtain the benefits of conservation agriculture for yield and soil quality. However, narrow (0.75–0.80 m width) and wide (1.50–1.60 m width) beds are commonly implemented without scientific evidence available as to whether the width of the beds affects crop yields. The objective of our study was therefore to evaluate two types of permanent beds, in maize (Zea mays L.), wheat (Triticum aestivum L.), and barley (Hordeum vulgare L.) production, in various agro-ecological regions of Mexico. The study included nine sites, of which six were rainfed and three had irrigation. Bed width did not significantly affect crop yield. Therefore, farmers can choose the bed width that best meets their practical needs. Some practical considerations include mechanical weeding (more access in narrow beds), fuel use (lower for reshaping wide beds), irrigation water use (in wide beds similar to irrigating alternate furrows in narrow beds), and residue management (option to concentrate residue in windrows at center of wide beds). Soil texture can also affect this choice, because it affects water infiltration and retention.