Slimming World (SW), a commercial weight management organisation, has designed a range of low energy-dense ready meals (LEDRMs) in line with their programme. This randomised crossover study compared commercially available equicaloric ready meals differing in energy density on satiety and food intake. It was hypothesised that the LEDRM would reduce energy intake (EI) whilst increasing fullness and reducing hunger compared to higher energy-dense ready meal (HEDRM, control). A total of 26 female participants (aged 18–65 years; body mass index of 28.8 ± 3.0 kg·m−2) attended two test days. The participants ate a standard breakfast, and four hours later, ate either a LEDRM or HEDRM at lunch. EI was measured four hours later at an ad libitum tea. Satiety measurements were recorded throughout the day using visual analogue scales and a weighed food diary was completed for the remainder of the day. The results revealed that the LEDRM reduced hunger and increased fullness (both p < 0.001). There was no difference in EI at the evening meal between the ready meals (p > 0.05), however, during the whole LEDRM testing day, the participants consumed significantly less fat (7.1%) and saturated fat (3.6%) (both p < 0.01), but significantly more carbohydrates, sugars, fibre, protein, and salt (all p < 0.01). The results indicate that the participants felt more satiated after consuming ready meals of the same energy content but larger portion size. Despite no significant difference in short-term EI between the ready meals, the results indicated that the LEDRM produced beneficial subjective satiety responses and, therefore, can help to improve the nutritional content of meals i.e., reduce saturated fat consumption.