diff --git a/PIL/EpsImagePlugin.py b/PIL/EpsImagePlugin.py
index 6f22308de..0b01ed652 100644
--- a/PIL/EpsImagePlugin.py
+++ b/PIL/EpsImagePlugin.py
@@ -418,7 +418,6 @@ Image.register_open(EpsImageFile.format, EpsImageFile, _accept)
 
 Image.register_save(EpsImageFile.format, _save)
 
-Image.register_extension(EpsImageFile.format, ".ps")
-Image.register_extension(EpsImageFile.format, ".eps")
+Image.register_extensions(EpsImageFile.format, [".ps", ".eps"])
 
 Image.register_mime(EpsImageFile.format, "application/postscript")
diff --git a/PIL/FitsStubImagePlugin.py b/PIL/FitsStubImagePlugin.py
index e3a7eb4a6..be926cadb 100644
--- a/PIL/FitsStubImagePlugin.py
+++ b/PIL/FitsStubImagePlugin.py
@@ -72,5 +72,4 @@ def _save(im, fp, filename):
 Image.register_open(FITSStubImageFile.format, FITSStubImageFile, _accept)
 Image.register_save(FITSStubImageFile.format, _save)
 
-Image.register_extension(FITSStubImageFile.format, ".fit")
-Image.register_extension(FITSStubImageFile.format, ".fits")
+Image.register_extensions(FITSStubImageFile.format, [".fit", ".fits"])
diff --git a/PIL/FliImagePlugin.py b/PIL/FliImagePlugin.py
index 52bebe80b..733d2d8f1 100644
--- a/PIL/FliImagePlugin.py
+++ b/PIL/FliImagePlugin.py
@@ -162,5 +162,4 @@ class FliImageFile(ImageFile.ImageFile):
 
 Image.register_open(FliImageFile.format, FliImageFile, _accept)
 
-Image.register_extension(FliImageFile.format, ".fli")
-Image.register_extension(FliImageFile.format, ".flc")
+Image.register_extensions(FliImageFile.format, [".fli", ".flc"])
diff --git a/PIL/FtexImagePlugin.py b/PIL/FtexImagePlugin.py
index 0d08f4cc4..9b9809062 100644
--- a/PIL/FtexImagePlugin.py
+++ b/PIL/FtexImagePlugin.py
@@ -91,5 +91,4 @@ def _validate(prefix):
 
 
 Image.register_open(FtexImageFile.format, FtexImageFile, _validate)
-Image.register_extension(FtexImageFile.format, ".ftc")
-Image.register_extension(FtexImageFile.format, ".ftu")
+Image.register_extensions(FtexImageFile.format, [".ftc", ".ftu"])
diff --git a/PIL/Hdf5StubImagePlugin.py b/PIL/Hdf5StubImagePlugin.py
index a5d6b1bc1..de4d5bb0c 100644
--- a/PIL/Hdf5StubImagePlugin.py
+++ b/PIL/Hdf5StubImagePlugin.py
@@ -69,5 +69,4 @@ def _save(im, fp, filename):
 Image.register_open(HDF5StubImageFile.format, HDF5StubImageFile, _accept)
 Image.register_save(HDF5StubImageFile.format, _save)
 
-Image.register_extension(HDF5StubImageFile.format, ".h5")
-Image.register_extension(HDF5StubImageFile.format, ".hdf")
+Image.register_extensions(HDF5StubImageFile.format, [".h5", ".hdf"])
diff --git a/PIL/Image.py b/PIL/Image.py
index d9660dce7..431041608 100644
--- a/PIL/Image.py
+++ b/PIL/Image.py
@@ -2728,6 +2728,16 @@ def register_extension(id, extension):
     """
     EXTENSION[extension.lower()] = id.upper()
 
+def register_extensions(id, extensions):
+    """
+    Registers image extensions.  This function should not be
+    used in application code.
+
+    :param id: An image format identifier.
+    :param extensions: A list of extensions used for this format.
+    """
+    for extension in extensions:
+        register_extension(id, extension)
 
 def registered_extensions():
     """
diff --git a/PIL/Jpeg2KImagePlugin.py b/PIL/Jpeg2KImagePlugin.py
index 101f55f76..c67cc14bf 100644
--- a/PIL/Jpeg2KImagePlugin.py
+++ b/PIL/Jpeg2KImagePlugin.py
@@ -269,12 +269,7 @@ def _save(im, fp, filename):
 Image.register_open(Jpeg2KImageFile.format, Jpeg2KImageFile, _accept)
 Image.register_save(Jpeg2KImageFile.format, _save)
 
-Image.register_extension(Jpeg2KImageFile.format, '.jp2')
-Image.register_extension(Jpeg2KImageFile.format, '.j2k')
-Image.register_extension(Jpeg2KImageFile.format, '.jpc')
-Image.register_extension(Jpeg2KImageFile.format, '.jpf')
-Image.register_extension(Jpeg2KImageFile.format, '.jpx')
-Image.register_extension(Jpeg2KImageFile.format, '.j2c')
+Image.register_extensions(Jpeg2KImageFile.format, [".jp2", ".j2k", ".jpc", ".jpf", ".jpx", ".j2c"])
 
 Image.register_mime(Jpeg2KImageFile.format, 'image/jp2')
 Image.register_mime(Jpeg2KImageFile.format, 'image/jpx')
diff --git a/PIL/JpegImagePlugin.py b/PIL/JpegImagePlugin.py
index d28c5e506..d286f793f 100644
--- a/PIL/JpegImagePlugin.py
+++ b/PIL/JpegImagePlugin.py
@@ -783,9 +783,6 @@ def jpeg_factory(fp=None, filename=None):
 Image.register_open(JpegImageFile.format, jpeg_factory, _accept)
 Image.register_save(JpegImageFile.format, _save)
 
-Image.register_extension(JpegImageFile.format, ".jfif")
-Image.register_extension(JpegImageFile.format, ".jpe")
-Image.register_extension(JpegImageFile.format, ".jpg")
-Image.register_extension(JpegImageFile.format, ".jpeg")
+Image.register_extensions(JpegImageFile.format, [".jfif", ".jpe", ".jpg", ".jpeg"])
 
 Image.register_mime(JpegImageFile.format, "image/jpeg")
diff --git a/PIL/MpegImagePlugin.py b/PIL/MpegImagePlugin.py
index bdc5e3689..fca7f9d9f 100644
--- a/PIL/MpegImagePlugin.py
+++ b/PIL/MpegImagePlugin.py
@@ -80,7 +80,6 @@ class MpegImageFile(ImageFile.ImageFile):
 
 Image.register_open(MpegImageFile.format, MpegImageFile)
 
-Image.register_extension(MpegImageFile.format, ".mpg")
-Image.register_extension(MpegImageFile.format, ".mpeg")
+Image.register_extensions(MpegImageFile.format, [".mpg", ".mpeg"])
 
 Image.register_mime(MpegImageFile.format, "video/mpeg")
diff --git a/PIL/PpmImagePlugin.py b/PIL/PpmImagePlugin.py
index b91f9912b..bd1b7a364 100644
--- a/PIL/PpmImagePlugin.py
+++ b/PIL/PpmImagePlugin.py
@@ -164,6 +164,4 @@ def _save(im, fp, filename):
 Image.register_open(PpmImageFile.format, PpmImageFile, _accept)
 Image.register_save(PpmImageFile.format, _save)
 
-Image.register_extension(PpmImageFile.format, ".pbm")
-Image.register_extension(PpmImageFile.format, ".pgm")
-Image.register_extension(PpmImageFile.format, ".ppm")
+Image.register_extensions(PpmImageFile.format, [".pbm", ".pgm", ".ppm"])
diff --git a/PIL/SgiImagePlugin.py b/PIL/SgiImagePlugin.py
index d5db91c2f..c96a8d821 100644
--- a/PIL/SgiImagePlugin.py
+++ b/PIL/SgiImagePlugin.py
@@ -149,9 +149,7 @@ Image.register_open(SgiImageFile.format, SgiImageFile, _accept)
 Image.register_save(SgiImageFile.format, _save)
 Image.register_mime(SgiImageFile.format, "image/sgi")
 Image.register_mime(SgiImageFile.format, "image/rgb")
-Image.register_extension(SgiImageFile.format, ".bw")
-Image.register_extension(SgiImageFile.format, ".rgb")
-Image.register_extension(SgiImageFile.format, ".rgba")
-Image.register_extension(SgiImageFile.format, ".sgi")
+
+Image.register_extensions(SgiImageFile.format, [".bw", ".rgb", ".rgba", ".sgi"])
 
 # End of file
diff --git a/PIL/TiffImagePlugin.py b/PIL/TiffImagePlugin.py
index bd66f4a7a..5786f8049 100644
--- a/PIL/TiffImagePlugin.py
+++ b/PIL/TiffImagePlugin.py
@@ -1792,7 +1792,6 @@ Image.register_open(TiffImageFile.format, TiffImageFile, _accept)
 Image.register_save(TiffImageFile.format, _save)
 Image.register_save_all(TiffImageFile.format, _save_all)
 
-Image.register_extension(TiffImageFile.format, ".tif")
-Image.register_extension(TiffImageFile.format, ".tiff")
+Image.register_extensions(TiffImageFile.format, [".tif", ".tiff"])
 
 Image.register_mime(TiffImageFile.format, "image/tiff")
diff --git a/PIL/WmfImagePlugin.py b/PIL/WmfImagePlugin.py
index c6c002ffd..fea436b3a 100644
--- a/PIL/WmfImagePlugin.py
+++ b/PIL/WmfImagePlugin.py
@@ -164,5 +164,4 @@ def _save(im, fp, filename):
 Image.register_open(WmfStubImageFile.format, WmfStubImageFile, _accept)
 Image.register_save(WmfStubImageFile.format, _save)
 
-Image.register_extension(WmfStubImageFile.format, ".wmf")
-Image.register_extension(WmfStubImageFile.format, ".emf")
+Image.register_extensions(WmfStubImageFile.format, [".wmf", ".emf"])