Introduction Branchial cleft cysts are the second most common congenital neck mass and can cause significant anxiety for patients and families despite their benign nature. Education through online patient education materials (PEMs) is critical for informing patients and reducing stress. We aimed to determine the content, quality, and readability of online PEMs related to branchial cleft cysts. Methods The search engine Google was used to collect the first 100 website results for the query "branchial cleft cyst." PEMs were included and assessed for content, quality via the DISCERN tool, and readability via Flesch Reading Ease Score (FRES), Flesch-Kincaid Reading Grade Level (FKGL), Gunning Frequency of Gobbledygook (GFOG), and Simple Measure of Gobbledygook (SMOG). Results Twenty-six websites containing PEMs related to branchial cleft cysts were assessed. Most websites were from universities or medical centers and did not contain any media. The mean DISCERN score was 49.3 (SD: 11.1, Median: 52.5), the mean FRES score was 51.9 (SD: 12.1, Median: 54.0), the mean FKGL score was 10.35 (SD: 2.52, Median: 9.95), the mean GFOG score was 13.32 (SD: 2.52, Median: 13.00), and the mean SMOG score was 10.25 (SD: 1.83, Median: 9.95). DISCERN was not significantly correlated with FRES, FKGL, GFOG, or SMOG. Conclusion Online PEMs related to branchial cleft cysts are consistently written above the National Institutes of Health (NIH) recommended sixth-grade reading level and are often of unsatisfactory overall quality. Writers of online PEMs for branchial cleft cysts should consider the readability and quality of their materials to improve patient education and reduce anxiety.