Groundwater and estuary water levels near Mill Creek and the Herring River in Wellfleet, Massachusetts, were measured from June 2017 to August 2022. The data contained in these datasets consist of tables of updated statistics provided in the original work by Mullaney and others (2020, Appendix 2) and associated data release by Mullaney and Barclay (2020). The data include summary tables of water-level statistics and summary tables of updated statistical coefficients for the models in the original work. The data release also includes the underlying input data sets for these statistical regression models and an update of table 2 from the larger work, which consists of summary statistics of water levels for the period of data analysis from 2017-06-01 to 2022-08-05. Mullaney, J.R., and Barclay, J.R., 2020, Data on Tidally Filtered Groundwater and Estuary Water Levels, and Climatological Data Near Mill Creek and the Herring River, Cape Cod, Wellfleet, Massachusetts, 2017-2018: U.S. Geological Survey data release, https://doi.org/10.5066/P9T167II. Mullaney, J.R., Barclay, J.R., Laabs, K.L., and Lavallee, K.D., 2020, Hydrogeology and interactions of groundwater and surface water near Mill Creek and the Herring River, Wellfleet, Massachusetts, 2017–18: U.S. Geological Survey Scientific Investigations Report 2019–5145, 60 p., https://doi.org/10.3133/sir20195145.