diff --git a/lib/utils/config/definitions.js b/lib/utils/config/definitions.js
index b47a46de85e2e..5bd13ac81a479 100644
--- a/lib/utils/config/definitions.js
+++ b/lib/utils/config/definitions.js
@@ -1782,7 +1782,10 @@ define('scope', {
   `,
   flatten (key, obj, flatOptions) {
     const value = obj[key]
-    flatOptions.projectScope = value && !/^@/.test(value) ? `@${value}` : value
+    const scope = value && !/^@/.test(value) ? `@${value}` : value
+    flatOptions.scope = scope
+    // projectScope is kept for compatibility with npm-registry-fetch
+    flatOptions.projectScope = scope
   },
 })
 
diff --git a/test/lib/utils/config/definitions.js b/test/lib/utils/config/definitions.js
index f6813a8bc0bb5..7af0b683987e4 100644
--- a/test/lib/utils/config/definitions.js
+++ b/test/lib/utils/config/definitions.js
@@ -488,15 +488,15 @@ t.test('maxSockets', t => {
   t.end()
 })
 
-t.test('projectScope', t => {
+t.test('scope', t => {
   const obj = { scope: 'asdf' }
   const flat = {}
   definitions.scope.flatten('scope', obj, flat)
-  t.strictSame(flat, { projectScope: '@asdf' }, 'prepend @ if needed')
+  t.strictSame(flat, { scope: '@asdf', projectScope: '@asdf' }, 'prepend @ if needed')
 
   obj.scope = '@asdf'
   definitions.scope.flatten('scope', obj, flat)
-  t.strictSame(flat, { projectScope: '@asdf' }, 'leave untouched if has @')
+  t.strictSame(flat, { scope: '@asdf', projectScope: '@asdf' }, 'leave untouched if has @')
 
   t.end()
 })