diff --git a/dev-requirements.txt b/dev-requirements.txt
index bf3b3dc..8bda125 100644
--- a/dev-requirements.txt
+++ b/dev-requirements.txt
@@ -77,7 +77,7 @@ opentelemetry-semantic-conventions==0.48b0
     # via
     #   elastic-opentelemetry (pyproject.toml)
     #   opentelemetry-sdk
-oteltest==0.15.0
+oteltest==0.21.0
     # via elastic-opentelemetry (pyproject.toml)
 packaging==24.1
     # via
diff --git a/pyproject.toml b/pyproject.toml
index 3b25117..a3c331b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -36,7 +36,7 @@ dependencies = [
 ]
 
 [project.optional-dependencies]
-dev = ["pytest", "pip-tools", "oteltest==0.15", "leb128"]
+dev = ["pytest", "pip-tools", "oteltest==0.21.0", "leb128"]
 
 [project.entry-points.opentelemetry_configurator]
 configurator = "elasticotel.distro:ElasticOpenTelemetryConfigurator"