diff --git a/src/sdr/plot/_spectral_estimation.py b/src/sdr/plot/_spectral_estimation.py
index 9e7edac1f..6b0008be9 100644
--- a/src/sdr/plot/_spectral_estimation.py
+++ b/src/sdr/plot/_spectral_estimation.py
@@ -64,7 +64,7 @@ def periodogram(
     sample_rate, sample_rate_provided = verify_sample_rate(sample_rate)
     # verify_isinstance(window, str, optional=True)
     verify_scalar(length, optional=True, int=True, positive=True)
-    verify_scalar(overlap, optional=True, int=True, positive=True)
+    verify_scalar(overlap, optional=True, int=True, non_negative=True)
     verify_scalar(fft, optional=True, int=True, positive=True)
     verify_literal(detrend, ["constant", "linear", False])
     verify_literal(average, ["mean", "median"])
@@ -174,7 +174,7 @@ def spectrogram(
     sample_rate, sample_rate_provided = verify_sample_rate(sample_rate)
     # verify_isinstance(window, str, optional=True)
     verify_scalar(length, optional=True, int=True, positive=True)
-    verify_scalar(overlap, optional=True, int=True, positive=True)
+    verify_scalar(overlap, optional=True, int=True, non_negative=True)
     verify_scalar(fft, optional=True, int=True, positive=True)
     verify_literal(detrend, ["constant", "linear", False])
     verify_isinstance(ax, plt.Axes, optional=True)