  A fiducial cross section for W$\gamma$ production in proton-proton collisions
is measured at a center-of-mass energy of 13 TeV in 137 fb$^{-1}$ of data
collected using the CMS detector at the LHC. The W $\to$ e$\nu$ and $\mu\nu$
decay modes are used in a maximum-likelihood fit to the lepton-photon invariant
mass distribution to extract the combined cross section. The measured cross
section is compared with theoretical expectations at next-to-leading order in
quantum chromodynamics. In addition, 95% confidence level intervals are
reported for anomalous triple-gauge couplings within the framework of effective
field theory.
