This file contains the time series of monthly evapotranspiration from the 13 HUC6 basins analyzed in the North American west and southwest which accompany the article 'GRACE-FO/ECOSTRESS synergies constrain fine-scale impacts on large-scale water balance'. The evapotranspiration is from 4 different sources: NLDAS-2 (publicly available to download online from https://disc.gsfc.nasa.gov/datasets?keywords=NLDAS), ECOSTRESS (publicly available to download online from https://lpdaacsvc.cr.usgs.gov/appeears/), GRACE-based (calculated with the water balance approach (Evapotranspiration = Precipitation - Runoff - change in total water storage) using publicly available MERRA-2 precipitation (https://disc.gsfc.nasa.gov/datasets?project=MERRA-2), United States Geological Survey streamflow (https://waterdata.usgs.gov/nwis/) and GRACE total water storage anomaly data (https://podaac.jpl.nasa.gov/dataset/TELLUS_GRAC-GRFO_MASCON_CRI_GRID_RL06_V2). The MODIS evapotranspiration timeseries were obtained from a dataset created by G. Halverson (reference: Halverson, G. (2018), Near Real-Time Monitoring of Global Evapotranspiration and its Application to Water Resource Management, California State University, Northridge, Northridge, California.) The evapotranspiration data has been aggregated to monthly for all data sets. For ECOSTRESS data which is daily, the monthly aggregate was created by averaging over all available ECOSTRESS observations in each month of record. The timeseries are available from 2003 to 2019 for ET-GRACE, MODIS and NLDAS-2, and available for 2019 for ECOSTRESS. Units are in mm / day.