diff --git a/services/circleci.js b/services/circleci.js
index cffdcc0..6b178d5 100644
--- a/services/circleci.js
+++ b/services/circleci.js
@@ -1,13 +1,11 @@
 // https://circleci.com/docs/2.0/env-vars/#built-in-environment-variables
 
-const {prNumber} = require('../lib/utils');
-
 module.exports = {
 	detect({env}) {
 		return Boolean(env.CIRCLECI);
 	},
 	configuration({env}) {
-		const pr = env.CIRCLE_PR_NUMBER || prNumber(env.CIRCLE_PULL_REQUEST || env.CI_PULL_REQUEST);
+		const pr = env.CIRCLE_PR_NUMBER;
 		const isPr = Boolean(pr);
 
 		return {
diff --git a/test/services/circleci.test.js b/test/services/circleci.test.js
index f70fb0b..eac089d 100644
--- a/test/services/circleci.test.js
+++ b/test/services/circleci.test.js
@@ -32,7 +32,7 @@ test('Push', t => {
 
 test('PR 1.0', t => {
 	t.deepEqual(
-		circle.configuration({env: Object.assign({}, env, {CIRCLE_BRANCH: 'pr-branch', CI_PULL_REQUEST: 'uri/pr/10'})}),
+		circle.configuration({env: Object.assign({}, env, {CIRCLE_BRANCH: 'pr-branch', CIRCLE_PR_NUMBER: '10'})}),
 		{
 			name: 'CircleCI',
 			service: 'circleci',
@@ -52,7 +52,7 @@ test('PR 1.0', t => {
 
 test('PR 2.0', t => {
 	t.deepEqual(
-		circle.configuration({env: Object.assign({}, env, {CIRCLE_BRANCH: 'pr-branch', CIRCLE_PULL_REQUEST: 'uri/pr/10'})}),
+		circle.configuration({env: Object.assign({}, env, {CIRCLE_BRANCH: 'pr-branch', CIRCLE_PR_NUMBER: '10'})}),
 		{
 			name: 'CircleCI',
 			service: 'circleci',