diff --git a/CHANGES.txt b/CHANGES.txt
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,5 +1,7 @@
 Changelog for Extra
 
+1.6.16, released 2019-05-25
+    Add atomicModifyIORef_ and atomicModifyIORef'_
 1.6.15, released 2019-04-22
     #45, add NonEmpty.Extra for extra appending functions
     #42, add fromMaybeM
diff --git a/extra.cabal b/extra.cabal
--- a/extra.cabal
+++ b/extra.cabal
@@ -1,7 +1,7 @@
 cabal-version:      >= 1.18
 build-type:         Simple
 name:               extra
-version:            1.6.15
+version:            1.6.16
 license:            BSD3
 license-file:       LICENSE
 category:           Development
@@ -15,7 +15,7 @@
     The module "Extra" documents all functions provided by this library. Modules such as "Data.List.Extra" provide extra functions over "Data.List" and also reexport "Data.List". Users are recommended to replace "Data.List" imports with "Data.List.Extra" if they need the extra functionality.
 homepage:           https://github.com/ndmitchell/extra#readme
 bug-reports:        https://github.com/ndmitchell/extra/issues
-tested-with:        GHC==8.6.4, GHC==8.4.4, GHC==8.2.2, GHC==8.0.2, GHC==7.10.3
+tested-with:        GHC==8.6.5, GHC==8.4.4, GHC==8.2.2, GHC==8.0.2, GHC==7.10.3
 
 extra-doc-files:
     CHANGES.txt
diff --git a/src/Data/IORef/Extra.hs b/src/Data/IORef/Extra.hs
--- a/src/Data/IORef/Extra.hs
+++ b/src/Data/IORef/Extra.hs
@@ -3,7 +3,8 @@
 --   Some of these functions are available in later versions of GHC, but not all.
 module Data.IORef.Extra(
     module Data.IORef,
-    writeIORef', atomicWriteIORef'
+    writeIORef', atomicWriteIORef',
+    atomicModifyIORef_, atomicModifyIORef'_
     ) where
 
 import Data.IORef
@@ -21,3 +22,12 @@
 atomicWriteIORef' ref x = do
     evaluate x
     atomicWriteIORef ref x
+
+
+-- | Variant of 'atomicModifyIORef' which ignores the return value
+atomicModifyIORef_ :: IORef a -> (a -> a) -> IO ()
+atomicModifyIORef_ r f = atomicModifyIORef r $ \v -> (f v, ())
+
+-- | Variant of 'atomicModifyIORef'' which ignores the return value
+atomicModifyIORef'_ :: IORef a -> (a -> a) -> IO ()
+atomicModifyIORef'_ r f = atomicModifyIORef' r $ \v -> (f v, ())
diff --git a/src/Extra.hs b/src/Extra.hs
--- a/src/Extra.hs
+++ b/src/Extra.hs
@@ -20,7 +20,7 @@
     fromLeft, fromRight, fromEither, fromLeft', fromRight', eitherToMaybe, maybeToEither, mapLeft, mapRight,
     -- * Data.IORef.Extra
     -- | Extra functions available in @"Data.IORef.Extra"@.
-    writeIORef', atomicWriteIORef',
+    writeIORef', atomicWriteIORef', atomicModifyIORef_, atomicModifyIORef'_,
     -- * Data.List.Extra
     -- | Extra functions available in @"Data.List.Extra"@.
     lower, upper, trim, trimStart, trimEnd, word1, line1, escapeHTML, escapeJSON, unescapeHTML, unescapeJSON, dropEnd, takeEnd, splitAtEnd, breakEnd, spanEnd, dropWhileEnd', takeWhileEnd, stripSuffix, stripInfix, stripInfixEnd, dropPrefix, dropSuffix, wordsBy, linesBy, breakOn, breakOnEnd, splitOn, split, chunksOf, notNull, list, unsnoc, cons, snoc, drop1, mconcatMap, groupSort, groupSortOn, groupSortBy, nubOrd, nubOrdBy, nubOrdOn, nubOn, groupOn, nubSort, nubSortBy, nubSortOn, maximumOn, minimumOn, disjoint, allSame, anySame, repeatedly, for, firstJust, concatUnzip, concatUnzip3, zipFrom, zipWithFrom, replace, merge, mergeBy,