diff --git a/packages/babel-core/src/config/full.js b/packages/babel-core/src/config/full.js
index af4212953f67..88c65ff882be 100644
--- a/packages/babel-core/src/config/full.js
+++ b/packages/babel-core/src/config/full.js
@@ -202,7 +202,7 @@ const loadDescriptor = makeWeakCache(
     if (typeof item.then === "function") {
       throw new Error(
         `You appear to be using an async plugin, ` +
-          `which your current version of Babel does not support.` +
+          `which your current version of Babel does not support. ` +
           `If you're using a published plugin, ` +
           `you may need to upgrade your @babel/core version.`,
       );
diff --git a/packages/babel-core/src/transformation/index.js b/packages/babel-core/src/transformation/index.js
index 3bfd82ab0353..a03c4db0cf2a 100644
--- a/packages/babel-core/src/transformation/index.js
+++ b/packages/babel-core/src/transformation/index.js
@@ -93,7 +93,7 @@ function transformFile(file: File, pluginPasses: PluginPasses): void {
         if (isThenable(result)) {
           throw new Error(
             `You appear to be using an plugin with an async .pre, ` +
-              `which your current version of Babel does not support.` +
+              `which your current version of Babel does not support. ` +
               `If you're using a published plugin, you may need to upgrade ` +
               `your @babel/core version.`,
           );
@@ -117,7 +117,7 @@ function transformFile(file: File, pluginPasses: PluginPasses): void {
         if (isThenable(result)) {
           throw new Error(
             `You appear to be using an plugin with an async .post, ` +
-              `which your current version of Babel does not support.` +
+              `which your current version of Babel does not support. ` +
               `If you're using a published plugin, you may need to upgrade ` +
               `your @babel/core version.`,
           );
diff --git a/packages/babel-traverse/src/path/context.js b/packages/babel-traverse/src/path/context.js
index 0057b1694d3f..faa5e9d3f15e 100644
--- a/packages/babel-traverse/src/path/context.js
+++ b/packages/babel-traverse/src/path/context.js
@@ -31,7 +31,7 @@ export function _call(fns?: Array<Function>): boolean {
     if (ret && typeof ret === "object" && typeof ret.then === "function") {
       throw new Error(
         `You appear to be using a plugin with an async traversal visitor, ` +
-          `which your current version of Babel does not support.` +
+          `which your current version of Babel does not support. ` +
           `If you're using a published plugin, you may need to upgrade ` +
           `your @babel/core version.`,
       );