diff --git a/Project.toml b/Project.toml
index 26bc650..cf60226 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "MIDI"
 uuid = "f57c4921-e30c-5f49-b073-3f2f2ada663e"
 repo = "https://github.com/JuliaMusic/MIDI.jl.git"
-version = "1.8.0"
+version = "1.8.1"
 
 [compat]
 julia = "1"
diff --git a/src/midifile.jl b/src/midifile.jl
index 535a197..062789e 100644
--- a/src/midifile.jl
+++ b/src/midifile.jl
@@ -84,7 +84,7 @@ Write a `MIDIFile` as a ".mid" file to the given filename.
 Create a `MIDIFile` directly from `notes`, using format 1.
 """
 function writeMIDIFile(filename::AbstractString, data::MIDIFile)
-    if length(filename) < 4 || lowercase(filename[end-3:end]) != ".mid"
+    if length(filename) < 4 || filename[end-3:end] != ".mid" && filename[end-3:end] != ".MID"
       filename *= ".mid"
     end