Low- and no-calorie sweeteners (LNCS) are a group of food additives characterized by their high sweetness intensity and virtually zero caloric content, attributes that make them potential substitutes for added sugars in processed foods and beverages. However, there is currently scarce information available about both the different LNCS used in food products available in Spain and their consumption patterns. Prompted by these reasons, the aim of this research work was to identify the presence and consumption of LNCS in food and beverages consumed by a representative sample of the Spanish adult population (n = 507). For this purpose, a Food Frequency Questionnaire was carried out. Overall, it was found that 4.5% of the foods and 22.3% of the beverages consumed by the surveyed population contained LNCS. The food groups that presented the highest percentage of daily servings containing LNCS were non-alcoholic beverages such as soft drinks and juices (36.1%); sugars and sweets such as chocolates, candies, or chewing gum (14.2%); milk and dairy products (7.0%); meat and derivative products (5.1%); cereals and derivatives (4.3%); appetizers (1.7%); and, finally, sauces and condiments such as ketchup or mustard (1.0%). The main LNCS consumed were acesulfame-K, sucralose, sorbitol, aspartame, and cyclamate, although their prevalence of use differs greatly among foods, beverages, or tabletop sweeteners. Our results show the great diversity of food groups that are currently including these compounds as ingredients. Consequently, there is a need for these food additives to be included in food composition databases, which should be regularly updated to include LNCS in order to facilitate their assessment and monitoring in dietary nutritional surveys.