diff --git a/bitbake/lib/bb/fetch2/__init__.py b/bitbake/lib/bb/fetch2/__init__.py
index 26ad388eb7..64451846c7 100644
--- a/bitbake/lib/bb/fetch2/__init__.py
+++ b/bitbake/lib/bb/fetch2/__init__.py
@@ -1642,7 +1642,7 @@ class Fetch(object):
             urls = self.urls
 
         network = self.d.getVar("BB_NO_NETWORK")
-        premirroronly = (self.d.getVar("BB_FETCH_PREMIRRORONLY") == "1")
+        premirroronly = bb.utils.to_boolean(self.d.getVar("BB_FETCH_PREMIRRORONLY"))
 
         for u in urls:
             ud = self.ud[u]
diff --git a/bitbake/lib/bb/fetch2/git.py b/bitbake/lib/bb/fetch2/git.py
index cf8bee7382..8185bf4db0 100644
--- a/bitbake/lib/bb/fetch2/git.py
+++ b/bitbake/lib/bb/fetch2/git.py
@@ -318,7 +318,7 @@ class Git(FetchMethod):
     def try_premirror(self, ud, d):
         # If we don't do this, updating an existing checkout with only premirrors
         # is not possible
-        if d.getVar("BB_FETCH_PREMIRRORONLY") is not None:
+        if bb.utils.to_boolean(d.getVar("BB_FETCH_PREMIRRORONLY")):
             return True
         if os.path.exists(ud.clonedir):
             return False
diff --git a/bitbake/lib/bb/fetch2/hg.py b/bitbake/lib/bb/fetch2/hg.py
index 936d043112..5a2985e16c 100644
--- a/bitbake/lib/bb/fetch2/hg.py
+++ b/bitbake/lib/bb/fetch2/hg.py
@@ -99,7 +99,7 @@ class Hg(FetchMethod):
     def try_premirror(self, ud, d):
         # If we don't do this, updating an existing checkout with only premirrors
         # is not possible
-        if d.getVar("BB_FETCH_PREMIRRORONLY") is not None:
+        if bb.utils.to_boolean(d.getVar("BB_FETCH_PREMIRRORONLY")):
             return True
         if os.path.exists(ud.moddir):
             return False