Equations are developed that allow the transmissivity and storage coefficient of an aquifer to be determined from recovery data taken from an observation well located at an arbitrary distance from the pumped well without the use of antecedent drawdown data. The fundamental result is in the form of a series based on the Theis recovery equation and up to the number of terms given is exact. The assumptions of radial flow in a confined aquifer that is homogeneous, isotropic, and semi‐infinite, which are implicit in the Theis development, are, of course, made in the current work as well. Two numerical examples using actual field data are given.

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