PurposeThis study aimed to develop a generalisable small and medium-sized enterprise (SME) brand equity scale and examine its relationship with consumer response factors.Design/methodology/approachThe study which was done in Thailand included three steps. First, brand communications of 40 successful SMEs and opinions of 56 consumers were collected by document analysis, interview and focus group for generating items and measurement of stimuli. Second, 838 consumers were surveyed to define the dimensions of the brand equity and the top SMEs. Third, surveys with 552 customers of the three most popular SMEs, one from each of the manufacturing, service and trade businesses, were conducted to examine the scale's invariance and its relationships with consumer responses.FindingsThe SME brand equity (SMEBE) scale included 23 items that were grouped into five components named brand awareness, functionality, authenticity, attentiveness and resonance. The scale is applicable across consumers that vary in their product involvement and brand engagement. The SMEBE significantly affected the brand's preference, loyalty and word-of-mouth.Research limitations/implicationsSince the SMEBE scale was tested with three brands, one from each of three business sectors, future studies should measure more than one SME for each business type. To allow for potential cultural characteristics that might affect the study, replications in diverse international settings are required.Practical implicationsSME managers should increase the awareness, functionality, authenticity, attentiveness and resonance of their brands as these components are essential for SMEBE, which, in turn, significantly affects consumer behaviour.Originality/valueThis study develops a ready-to-use SMEBE scale and introduces a practical research design for quantitative research on SME branding.