diff --git a/build.sbt b/build.sbt
index 53a0ee2..6d6c30e 100644
--- a/build.sbt
+++ b/build.sbt
@@ -29,7 +29,7 @@ lazy val compilerOptions = Seq(
 val testDependencies = Seq(
   "org.mockito" % "mockito-all" % "1.10.19",
   "org.scalacheck" %% "scalacheck" % "1.14.1",
-  "org.scalatest" %% "scalatest" % "3.0.8"
+  "org.scalatest" %% "scalatest" % "3.1.2"
 )
 
 val baseSettings = Seq(
diff --git a/examples/src/test/scala/io/finch/oauth2/OAuth2Spec.scala b/examples/src/test/scala/io/finch/oauth2/OAuth2Spec.scala
index 5d69282..19c6fd3 100644
--- a/examples/src/test/scala/io/finch/oauth2/OAuth2Spec.scala
+++ b/examples/src/test/scala/io/finch/oauth2/OAuth2Spec.scala
@@ -2,9 +2,10 @@ package io.finch.oauth2
 
 import com.twitter.finagle.http.Status
 import io.finch.Input
-import org.scalatest.{FlatSpec, Matchers}
+import org.scalatest.flatspec.AnyFlatSpec
+import org.scalatest.matchers.should.Matchers
 
-class OAuth2Spec extends FlatSpec with Matchers {
+class OAuth2Spec extends AnyFlatSpec with Matchers {
   import Main._
 
   behavior of "the token-generating endpoint"
diff --git a/oauth2/src/test/scala/io/finch/oauth2/OAuth2Spec.scala b/oauth2/src/test/scala/io/finch/oauth2/OAuth2Spec.scala
index 4061244..39ee37d 100644
--- a/oauth2/src/test/scala/io/finch/oauth2/OAuth2Spec.scala
+++ b/oauth2/src/test/scala/io/finch/oauth2/OAuth2Spec.scala
@@ -7,11 +7,12 @@ import com.twitter.util.Future
 import io.finch._
 import io.finch.catsEffect._
 import org.mockito.Mockito._
-import org.scalatest.{FlatSpec, Matchers}
-import org.scalatest.mockito.MockitoSugar
-import org.scalatest.prop.Checkers
+import org.scalatestplus.mockito.MockitoSugar
+import org.scalatestplus.scalacheck.Checkers
+import org.scalatest.flatspec.AnyFlatSpec
+import org.scalatest.matchers.should.Matchers
 
-class OAuth2Spec extends FlatSpec with Matchers with Checkers with MockitoSugar {
+class OAuth2Spec extends AnyFlatSpec with Matchers with Checkers with MockitoSugar {
 
   behavior of "OAuth2"