Analytical recovery is the concentration of an analyte measured in a water-quality sample expressed as a percentage of the known concentration added to the sample (Mueller and others, 2015). Analytical recovery (hereafter referred to as “recovery”) can be used to understand method bias and variability and to assess the temporal changes in a method over time (Martin and others, 2009). This data set includes two tables: one table of field spike recovery data and one table of lab reagent spike recovery data. The table of field spike recovery data includes results from paired environmental and spike samples collected by the National Water Quality Program, National Water-Quality Assessment (NAWQA) Project in surface water and groundwater. These samples were collected as part of the NAWQA Project’s National Water Quality Network: Rivers and Streams assessment, Regional Stream Quality Assessment studies and in multiple groundwater networks following standard practices (Mueller and others, 1997). This table includes environmental and spike water-quality sample data stored in the USGS National Water Information System (NWIS) database (https://dx.doi.org/10.5066/F7P55KJN). Concentrations of pesticides in spike samples, while stored in the NWIS database, are not publically available. The calculation of recovery based on these field sample data is outlined in Mueller and others (2015). Lab reagent spikes are pesticide-free reagent water spiked with a known concentration of pesticide. Lab reagent spikes are prepared in the lab and their recovery can be directly measured. The table of lab reagent spike data contains quality control sample information stored in the USGS National Water Quality Laboratory (NWQL) database. Both tables include fields for data-quality indicators that are described in the data processing steps of this metadata file. These tables were developed in order to support a USGS Scientific Investigations Report with the working title “Considerations for the Preparation of Pesticide Data Analyzed with National Water Quality Laboratory Schedule 2437”. Martin, J.D., Stone, W.W, Wydoski, D.S., and Sandstrom, M.W., 2009, Adjustment of pesticide concentrations for temporal changes in analytical recovery, 1992–2006: U.S. Geological Survey Scientific Investigations Report 2009–5189, 23 p. plus appendixes. Mueller, D.K., Schertz, T.L., Martin, J.D., and Sandstrom, M.W., 2015, Design, analysis, and interpretation of field quality-control data for water-sampling projects: U.S. Geological Survey Techniques and Methods, book 4, chap. C4, 54 p., https://dx.doi.org/10.3133/tm4C4. Mueller, D.K., Martin, J.D. and Lopes, T.J., 1997, Quality-Control Design for Surface-Water Sampling in the National Water-Quality Assessment Program: U.S. Geological Survey Open-File Report 97-223, 8 p. plus appendixes.