diff --git a/Lib/fontTools/varLib/merger.py b/Lib/fontTools/varLib/merger.py
index ef9860999..5a3a4f343 100644
--- a/Lib/fontTools/varLib/merger.py
+++ b/Lib/fontTools/varLib/merger.py
@@ -263,7 +263,7 @@ def merge(merger, self, lst):
# If all have same coverage table and all are format 1,
coverageGlyphs = self.Coverage.glyphs
if all(v.Format == 1 for v in lst) and all(coverageGlyphs == v.Coverage.glyphs for v in lst):
- self.Value = otBase.ValueRecord(valueFormat)
+ self.Value = otBase.ValueRecord(valueFormat, self.Value)
if valueFormat != 0:
merger.mergeThings(self.Value, [v.Value for v in lst])
self.ValueFormat = self.Value.getFormat()
diff --git a/Tests/varLib/instancer/data/SinglePos.ttx b/Tests/varLib/instancer/data/SinglePos.ttx
new file mode 100644
index 000000000..64ffd9f51
--- /dev/null
+++ b/Tests/varLib/instancer/data/SinglePos.ttx
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