diff --git a/Lib/ufoLib/glifLib.py b/Lib/ufoLib/glifLib.py
index e3d5ee086..1cb2d7dcc 100755
--- a/Lib/ufoLib/glifLib.py
+++ b/Lib/ufoLib/glifLib.py
@@ -548,10 +548,7 @@ def readGlyphFromString(aString, glyphObject=None, pointPen=None, formatVersions
 	_readGlyphFromTree(tree, glyphObject, pointPen, formatVersions=formatVersions, validate=validate)
 
 
-# we use a custom XML declaration for backward compatibility with older
-# ufoLib versions which would write it using double quotes.
-# https://github.com/unified-font-object/ufoLib/issues/158
-XML_DECLARATION = b"""<?xml version="1.0" encoding="UTF-8"?>\n"""
+_XML_DECLARATION = plistlib.XML_DECLARATION + b"\n"
 
 
 def _writeGlyphToBytes(
@@ -597,7 +594,7 @@ def _writeGlyphToBytes(
 	if getattr(glyphObject, "lib", None):
 		_writeLib(glyphObject, root, validate)
 	# return the text
-	data = XML_DECLARATION + etree.tostring(
+	data = _XML_DECLARATION + etree.tostring(
 		root, encoding="utf-8", xml_declaration=False, pretty_print=True
 	)
 	return data
diff --git a/Lib/ufoLib/plistlib.py b/Lib/ufoLib/plistlib.py
index 00b9331d5..7cf080a07 100644
--- a/Lib/ufoLib/plistlib.py
+++ b/Lib/ufoLib/plistlib.py
@@ -13,6 +13,11 @@ from lxml import etree
 from fontTools.misc.py23 import unicode, basestring, tounicode
 
 
+# we use a custom XML declaration for backward compatibility with older
+# ufoLib versions which would write it using double quotes.
+# https://github.com/unified-font-object/ufoLib/issues/158
+XML_DECLARATION = b"""<?xml version="1.0" encoding="UTF-8"?>"""
+
 PLIST_DOCTYPE = (
     '<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" '
     '"http://www.apple.com/DTDs/PropertyList-1.0.dtd">'
@@ -328,11 +333,14 @@ def dump(value, fp, sort_keys=True, skipkeys=False, _pretty_print=True):
     root = etree.Element("plist", version="1.0")
     root.append(totree(value, sort_keys=sort_keys, skipkeys=skipkeys))
     tree = etree.ElementTree(root)
+    fp.write(XML_DECLARATION)
+    if _pretty_print:
+        fp.write(b"\n")
     tree.write(
         fp,
         encoding="utf-8",
         pretty_print=_pretty_print,
-        xml_declaration=True,
+        xml_declaration=False,
         doctype=PLIST_DOCTYPE,
     )
 
diff --git a/Lib/ufoLib/test/test_glifLib.py b/Lib/ufoLib/test/test_glifLib.py
index 62e2d5531..c744510ef 100644
--- a/Lib/ufoLib/test/test_glifLib.py
+++ b/Lib/ufoLib/test/test_glifLib.py
@@ -6,7 +6,7 @@ from io import open
 from ufoLib.test.testSupport import getDemoFontGlyphSetPath
 from ufoLib.glifLib import (
 	GlyphSet, glyphNameToFileName, readGlyphFromString, writeGlyphToString,
-	XML_DECLARATION,
+	_XML_DECLARATION,
 )
 
 GLYPHSETDIR = getDemoFontGlyphSetPath()
@@ -160,7 +160,7 @@ class ReadWriteFuncTest(unittest.TestCase):
 
 	def testXmlDeclaration(self):
 		s = writeGlyphToString("a", _Glyph())
-		self.assertTrue(s.startswith(XML_DECLARATION.decode("utf-8")))
+		self.assertTrue(s.startswith(_XML_DECLARATION.decode("utf-8")))
 
 
 if __name__ == "__main__":