Maize is the most important food crop in Swaziland, and is produced by over 90% of smallholder farmers on Swazi Nation Land. Excluding environmental variables, yield losses in maize are caused mainly by competition from weeds. Herbicidal weed control is a promising way to control weeds at initial stages of crop growth with the appropriate choice and rate of herbicides. An experiment was conducted at the Malkerns Research Station and Mangcongco experimental site during the 2014/2015 cropping season. The main objective of the study was to evaluate the efficacy of available herbicides for weed control and maize grain yield. There were 16 treatments; Four herbicides were used; Bladex Plus, Gardomil Gold, Lumax and 2,4-D Amine 480. Four rates of application were used; Control (hand-weeding), rate of recommendation based on the % clay content in the soil, half and full the rate recommended by the local retailers. A randomised complete block design (RCBD) experiment in a factorial arrangement, replicated four times was used. Highest efficacy of broadleaves in Malkerns was 97% when the herbicide Lumax at the rate recommended as per % clay content in the soil and in Mangcongco it was 76% with the use of herbicide Gardomil Gold at the full rate recommended by retailers. Weed control efficiencies for grasses in both sites at all rates were negative. Gardomil Gold was efficient in controlling sedges in both sites, at the full rate of the retailer’s recommendation (60%) in Malkerns and at half the rate recommended by retailers (28%) in Mangcongco. In Malkerns the highest grain yield was 8741 kg/ha with the treatment 2,4-D Amine 480 at the full rate recommended by retailers. In Mangcongco, the highest grain yield was 4427 kg/ha with the treatment Bladex Plus at the rate recommended based on % clay content in the soil. The highest grain yield in Malkerns was 8741 kg/ha when 2,4-D Amine 480 was used, at full rate recommended by retailer’s (2 L/ha). While in Mangcongco, Bladex Plus, at the rate based on the % clay content in the soil (4.3 L/ha) had the highest yield of 4427 kg/ha. Hence herbicides and rates with higher yields are recommended for each site.