diff --git a/overlay-x86-agz/make.conf b/overlay-x86-agz/make.conf
index 3f6b94f..ab0c0ee 100644
--- a/overlay-x86-agz/make.conf
+++ b/overlay-x86-agz/make.conf
@@ -3,6 +3,3 @@
 
 USE="${USE} compat_wireless gobi agz stats_opt_in synaptics is_touchpad lockvt"
 KCONFIG="atom"
-
-# PORTAGE_BINHOST is pulled in from prebuilt.conf
-source prebuilt.conf
diff --git a/overlay-x86-agz/prebuilt.conf b/overlay-x86-agz/prebuilt.conf
deleted file mode 100644
index 543a2c4..0000000
--- a/overlay-x86-agz/prebuilt.conf
+++ /dev/null
@@ -1 +0,0 @@
-PORTAGE_BINHOST="http://chromeos-prebuilt/board/x86-agz/master-07.03.11.135342/packages/"
diff --git a/overlay-x86-alex/make.conf b/overlay-x86-alex/make.conf
index d4e532b..8efe42b 100644
--- a/overlay-x86-alex/make.conf
+++ b/overlay-x86-alex/make.conf
@@ -8,7 +8,3 @@
 LIGHT_SENSOR_NAME=skateFN
 LIGHT_SENSOR_BUS=2
 LIGHT_SENSOR_ADDRESS=0x29
-
-
-# PORTAGE_BINHOST is pulled in from prebuilt.conf
-source prebuilt.conf
diff --git a/overlay-x86-alex/prebuilt.conf b/overlay-x86-alex/prebuilt.conf
deleted file mode 100644
index 507ed16..0000000
--- a/overlay-x86-alex/prebuilt.conf
+++ /dev/null
@@ -1 +0,0 @@
-PORTAGE_BINHOST="http://chromeos-prebuilt/board/x86-alex/master-19.01.11.152857/packages/"
diff --git a/overlay-x86-dogfood/make.conf b/overlay-x86-dogfood/make.conf
index 5f59d30..17fb371 100644
--- a/overlay-x86-dogfood/make.conf
+++ b/overlay-x86-dogfood/make.conf
@@ -3,6 +3,3 @@
 
 USE="${USE} compat_wireless gobi google_qdl dogfood modemmanager novatel_gobi samsung_gobi stats_opt_in synaptics ps_touchpad"
 KCONFIG="atom"
-
-# PORTAGE_BINHOST is pulled in from prebuilt.conf
-source prebuilt.conf
diff --git a/overlay-x86-dogfood/prebuilt.conf b/overlay-x86-dogfood/prebuilt.conf
deleted file mode 100644
index 9b0951d..0000000
--- a/overlay-x86-dogfood/prebuilt.conf
+++ /dev/null
@@ -1 +0,0 @@
-PORTAGE_BINHOST="http://chromeos-prebuilt/board/x86-dogfood/master-26.01.11.214510/packages/"
diff --git a/overlay-x86-mario/make.conf b/overlay-x86-mario/make.conf
index a973310..675ac3c 100644
--- a/overlay-x86-mario/make.conf
+++ b/overlay-x86-mario/make.conf
@@ -7,6 +7,3 @@
 # If nonzero in length, this is used by the chromeos-init ebuild to update the
 # /etc/init/light-sensor.conf file.
 LIGHT_SENSOR_TUNEVAL=15000
-
-# PORTAGE_BINHOST is pulled in from prebuilt.conf
-source prebuilt.conf
diff --git a/overlay-x86-mario/prebuilt.conf b/overlay-x86-mario/prebuilt.conf
deleted file mode 100644
index e5adeb4..0000000
--- a/overlay-x86-mario/prebuilt.conf
+++ /dev/null
@@ -1 +0,0 @@
-PORTAGE_BINHOST="http://chromeos-prebuilt/board/x86-mario/master-07.03.11.134424/packages/"