diff --git a/ghcide/src/Development/IDE/GHC/Warnings.hs b/ghcide/src/Development/IDE/GHC/Warnings.hs
index 68c52cf982..7ff1bc8e4d 100644
--- a/ghcide/src/Development/IDE/GHC/Warnings.hs
+++ b/ghcide/src/Development/IDE/GHC/Warnings.hs
@@ -3,14 +3,16 @@
 
 module Development.IDE.GHC.Warnings(withWarnings) where
 
+import Data.List
 import ErrUtils
-import GhcPlugins as GHC hiding (Var)
+import GhcPlugins as GHC hiding (Var, (<>))
 
 import           Control.Concurrent.Extra
 import qualified           Data.Text as T
 
 import           Development.IDE.Types.Diagnostics
 import           Development.IDE.GHC.Error
+import           Language.Haskell.LSP.Types (NumberOrString (StringValue))
 
 
 -- | Take a GHC monadic action (e.g. @typecheckModule pm@ for some
@@ -27,8 +29,19 @@ withWarnings diagSource action = do
   warnings <- newVar []
   let newAction :: DynFlags -> WarnReason -> Severity -> SrcSpan -> PprStyle -> SDoc -> IO ()
       newAction dynFlags wr _ loc style msg = do
-        let wr_d = fmap (wr,) $ diagFromErrMsg diagSource dynFlags $ mkWarnMsg dynFlags loc (queryQual style) msg
+        let wr_d = map ((wr,) . third3 (attachReason wr)) $ diagFromErrMsg diagSource dynFlags $ mkWarnMsg dynFlags loc (queryQual style) msg
         modifyVar_ warnings $ return . (wr_d:)
   res <- action $ \x -> x{ms_hspp_opts = (ms_hspp_opts x){log_action = newAction}}
   warns <- readVar warnings
   return (reverse $ concat warns, res)
+
+attachReason :: WarnReason -> Diagnostic -> Diagnostic
+attachReason wr d = d{_code = StringValue <$> showReason wr}
+ where
+  showReason = \case
+    NoReason -> Nothing
+    Reason flag -> showFlag flag
+    ErrReason flag -> showFlag =<< flag
+
+showFlag :: WarningFlag -> Maybe T.Text
+showFlag flag = ("-W" <>) . T.pack . flagSpecName <$> find ((== flag) . flagSpecFlag) wWarningFlags
diff --git a/ghcide/src/Development/IDE/Plugin/CodeAction.hs b/ghcide/src/Development/IDE/Plugin/CodeAction.hs
index 2422ccc64d..f6ac664aa5 100644
--- a/ghcide/src/Development/IDE/Plugin/CodeAction.hs
+++ b/ghcide/src/Development/IDE/Plugin/CodeAction.hs
@@ -203,6 +203,7 @@ suggestAction packageExports ideOptions parsedModule text diag = concat
     ++ suggestNewImport packageExports pm diag
     ++ suggestDeleteUnusedBinding pm text diag
     ++ suggestExportUnusedTopBinding text pm diag
+    ++ suggestDisableWarning pm text diag
     | Just pm <- [parsedModule]
     ] ++
     suggestFillHole diag                   -- Lowest priority
@@ -226,6 +227,15 @@ findInstanceHead df instanceHead decls =
 findDeclContainingLoc :: Position -> [Located a] -> Maybe (Located a)
 findDeclContainingLoc loc = find (\(L l _) -> loc `isInsideSrcSpan` l)
 
+suggestDisableWarning :: ParsedModule -> Maybe T.Text -> Diagnostic -> [(T.Text, [TextEdit])]
+suggestDisableWarning pm contents Diagnostic{..}
+    | Just (StringValue (T.stripPrefix "-W" -> Just w)) <- _code =
+        pure
+            ( "Disable \"" <> w <> "\" warnings"
+            , [TextEdit (endOfModuleHeader pm contents) $ "{-# OPTIONS_GHC -Wno-" <> w <> " #-}\n"]
+            )
+    | otherwise = []
+
 suggestRemoveRedundantImport :: ParsedModule -> Maybe T.Text -> Diagnostic -> [(T.Text, [TextEdit])]
 suggestRemoveRedundantImport ParsedModule{pm_parsed_source = L _  HsModule{hsmodImports}} contents Diagnostic{_range=_range,..}
 --     The qualified import of ‘many’ from module ‘Control.Applicative’ is redundant
@@ -1247,3 +1257,17 @@ importStyles IdentInfo {parent, rendered, isDatacon}
 renderImportStyle :: ImportStyle -> T.Text
 renderImportStyle (ImportTopLevel x) = x
 renderImportStyle (ImportViaParent x p) = p <> "(" <> x <> ")"
+
+-- | Find the first non-blank line before the first of (module name / imports / declarations).
+-- Useful for inserting pragmas.
+endOfModuleHeader :: ParsedModule -> Maybe T.Text -> Range
+endOfModuleHeader pm contents =
+    let mod = unLoc $ pm_parsed_source pm
+        modNameLoc = getLoc <$> hsmodName mod
+        firstImportLoc = getLoc <$> listToMaybe (hsmodImports mod)
+        firstDeclLoc = getLoc <$> listToMaybe (hsmodDecls mod)
+        line = fromMaybe 0 $ firstNonBlankBefore . _line . _start =<< srcSpanToRange =<<
+            modNameLoc <|> firstImportLoc <|> firstDeclLoc
+        firstNonBlankBefore n = (n -) . fromMaybe 0 . findIndex (not . T.null) . reverse . take n . T.lines <$> contents
+        loc = Position line 0
+     in Range loc loc
diff --git a/ghcide/test/exe/Main.hs b/ghcide/test/exe/Main.hs
index fb6befc6d2..6101e29e11 100644
--- a/ghcide/test/exe/Main.hs
+++ b/ghcide/test/exe/Main.hs
@@ -14,7 +14,7 @@ import Control.Applicative.Combinators
 import Control.Exception (bracket_, catch)
 import qualified Control.Lens as Lens
 import Control.Monad
-import Control.Monad.IO.Class (liftIO)
+import Control.Monad.IO.Class (MonadIO, liftIO)
 import Data.Aeson (FromJSON, Value, toJSON)
 import qualified Data.Binary as Binary
 import Data.Default
@@ -64,6 +64,7 @@ import Development.IDE.Plugin.Test (WaitForIdeRuleResult(..), TestRequest(BlockS
 import Control.Monad.Extra (whenJust)
 import qualified Language.Haskell.LSP.Types.Lens as L
 import Control.Lens ((^.))
+import Data.Functor
 
 main :: IO ()
 main = do
@@ -676,6 +677,7 @@ codeActionTests = testGroup "code actions"
   , removeImportTests
   , extendImportTests
   , suggestImportTests
+  , disableWarningTests
   , fixConstructorImportTests
   , importRenameActionTests
   , fillTypedHoleTests
@@ -881,9 +883,8 @@ removeImportTests = testGroup "remove import actions"
             ]
       docB <- createDoc "ModuleB.hs" "haskell" contentB
       _ <- waitForDiagnostics
-      [CACodeAction action@CodeAction { _title = actionTitle }, _]
-          <- getCodeActions docB (Range (Position 2 0) (Position 2 5))
-      liftIO $ "Remove import" @=? actionTitle
+      action <- assertJust "Code action not found" . firstJust (caWithTitle "Remove import")
+        =<< getCodeActions docB (Range (Position 2 0) (Position 2 5))
       executeCodeAction action
       contentAfterAction <- documentContents docB
       let expectedContentAfterAction = T.unlines
@@ -907,9 +908,8 @@ removeImportTests = testGroup "remove import actions"
             ]
       docB <- createDoc "ModuleB.hs" "haskell" contentB
       _ <- waitForDiagnostics
-      [CACodeAction action@CodeAction { _title = actionTitle }, _]
-          <- getCodeActions docB (Range (Position 2 0) (Position 2 5))
-      liftIO $ "Remove import" @=? actionTitle
+      action <- assertJust "Code action not found" . firstJust (caWithTitle "Remove import")
+        =<< getCodeActions docB (Range (Position 2 0) (Position 2 5))
       executeCodeAction action
       contentAfterAction <- documentContents docB
       let expectedContentAfterAction = T.unlines
@@ -936,9 +936,8 @@ removeImportTests = testGroup "remove import actions"
             ]
       docB <- createDoc "ModuleB.hs" "haskell" contentB
       _ <- waitForDiagnostics
-      [CACodeAction action@CodeAction { _title = actionTitle }, _]
-          <- getCodeActions docB (Range (Position 2 0) (Position 2 5))
-      liftIO $ "Remove stuffA, stuffC from import" @=? actionTitle
+      action <- assertJust "Code action not found" . firstJust (caWithTitle "Remove stuffA, stuffC from import")
+        =<< getCodeActions docB (Range (Position 2 0) (Position 2 5))
       executeCodeAction action
       contentAfterAction <- documentContents docB
       let expectedContentAfterAction = T.unlines
@@ -965,9 +964,8 @@ removeImportTests = testGroup "remove import actions"
             ]
       docB <- createDoc "ModuleB.hs" "haskell" contentB
       _ <- waitForDiagnostics
-      [CACodeAction action@CodeAction { _title = actionTitle }, _]
-          <- getCodeActions docB (Range (Position 2 0) (Position 2 5))
-      liftIO $ "Remove !!, <?> from import" @=? actionTitle
+      action <- assertJust "Code action not found" . firstJust (caWithTitle "Remove !!, <?> from import")
+        =<< getCodeActions docB (Range (Position 2 0) (Position 2 5))
       executeCodeAction action
       contentAfterAction <- documentContents docB
       let expectedContentAfterAction = T.unlines
@@ -993,9 +991,8 @@ removeImportTests = testGroup "remove import actions"
             ]
       docB <- createDoc "ModuleB.hs" "haskell" contentB
       _ <- waitForDiagnostics
-      [CACodeAction action@CodeAction { _title = actionTitle }, _]
-          <- getCodeActions docB (Range (Position 2 0) (Position 2 5))
-      liftIO $ "Remove A from import" @=? actionTitle
+      action <- assertJust "Code action not found" . firstJust (caWithTitle "Remove A from import")
+        =<< getCodeActions docB (Range (Position 2 0) (Position 2 5))
       executeCodeAction action
       contentAfterAction <- documentContents docB
       let expectedContentAfterAction = T.unlines
@@ -1020,9 +1017,8 @@ removeImportTests = testGroup "remove import actions"
             ]
       docB <- createDoc "ModuleB.hs" "haskell" contentB
       _ <- waitForDiagnostics
-      [CACodeAction action@CodeAction { _title = actionTitle }, _]
-          <- getCodeActions docB (Range (Position 2 0) (Position 2 5))
-      liftIO $ "Remove A, E, F from import" @=? actionTitle
+      action <- assertJust "Code action not found" . firstJust (caWithTitle "Remove A, E, F from import")
+        =<< getCodeActions docB (Range (Position 2 0) (Position 2 5))
       executeCodeAction action
       contentAfterAction <- documentContents docB
       let expectedContentAfterAction = T.unlines
@@ -1044,9 +1040,8 @@ removeImportTests = testGroup "remove import actions"
             ]
       docB <- createDoc "ModuleB.hs" "haskell" contentB
       _ <- waitForDiagnostics
-      [CACodeAction action@CodeAction { _title = actionTitle }, _]
-          <- getCodeActions docB (Range (Position 2 0) (Position 2 5))
-      liftIO $ "Remove import" @=? actionTitle
+      action <- assertJust "Code action not found" . firstJust (caWithTitle "Remove import")
+        =<< getCodeActions docB (Range (Position 2 0) (Position 2 5))
       executeCodeAction action
       contentAfterAction <- documentContents docB
       let expectedContentAfterAction = T.unlines
@@ -1069,9 +1064,8 @@ removeImportTests = testGroup "remove import actions"
             ]
       doc <- createDoc "ModuleC.hs" "haskell" content
       _ <- waitForDiagnostics
-      [_, _, _, _, CACodeAction action@CodeAction { _title = actionTitle }]
-          <- getCodeActions doc (Range (Position 2 0) (Position 2 5))
-      liftIO $ "Remove all redundant imports" @=? actionTitle
+      action <- assertJust "Code action not found" . firstJust (caWithTitle "Remove all redundant imports")
+        =<< getCodeActions doc (Range (Position 2 0) (Position 2 5))
       executeCodeAction action
       contentAfterAction <- documentContents doc
       let expectedContentAfterAction = T.unlines
@@ -1087,6 +1081,10 @@ removeImportTests = testGroup "remove import actions"
             ]
       liftIO $ expectedContentAfterAction @=? contentAfterAction
   ]
+  where
+    caWithTitle t = \case
+      CACodeAction a@CodeAction{_title} -> guard (_title == t) >> Just a
+      _ -> Nothing
 
 extendImportTests :: TestTree
 extendImportTests = testGroup "extend import actions"
@@ -1441,6 +1439,57 @@ suggestImportTests = testGroup "suggest import actions"
           else
               liftIO $ [_title | CACodeAction CodeAction{_title} <- actions, _title == newImp ] @?= []
 
+disableWarningTests :: TestTree
+disableWarningTests =
+  testGroup "disable warnings" $
+    [
+      ( "missing-signatures"
+      , T.unlines
+          [ "{-# OPTIONS_GHC -Wall #-}"
+          , "main = putStrLn \"hello\""
+          ]
+      , T.unlines
+          [ "{-# OPTIONS_GHC -Wall #-}"
+          , "{-# OPTIONS_GHC -Wno-missing-signatures #-}"
+          , "main = putStrLn \"hello\""
+          ]
+      )
+    ,
+      ( "unused-imports"
+      , T.unlines
+          [ "{-# OPTIONS_GHC -Wall #-}"
+          , ""
+          , ""
+          , "module M where"
+          , ""
+          , "import Data.Functor"
+          ]
+      , T.unlines
+          [ "{-# OPTIONS_GHC -Wall #-}"
+          , "{-# OPTIONS_GHC -Wno-unused-imports #-}"
+          , ""
+          , ""
+          , "module M where"
+          , ""
+          , "import Data.Functor"
+          ]
+      )
+    ]
+      <&> \(warning, initialContent, expectedContent) -> testSession (T.unpack warning) $ do
+        doc <- createDoc "Module.hs" "haskell" initialContent
+        _ <- waitForDiagnostics
+        codeActs <- mapMaybe caResultToCodeAct <$> getCodeActions doc (Range (Position 0 0) (Position 0 0))
+        case find (\CodeAction{_title} -> _title == "Disable \"" <> warning <> "\" warnings") codeActs of
+          Nothing -> liftIO $ assertFailure "No code action with expected title"
+          Just action -> do
+            executeCodeAction action
+            contentAfterAction <- documentContents doc
+            liftIO $ expectedContent @=? contentAfterAction
+ where
+  caResultToCodeAct = \case
+    CACommand _ -> Nothing
+    CACodeAction c -> Just c
+
 insertNewDefinitionTests :: TestTree
 insertNewDefinitionTests = testGroup "insert new definition actions"
   [ testSession "insert new function definition" $ do
@@ -2192,7 +2241,12 @@ removeRedundantConstraintsTests = let
     doc <- createDoc "Testing.hs" "haskell" code
     _ <- waitForDiagnostics
     actionsOrCommands <- getCodeActions doc (Range (Position 4 0) (Position 4 maxBound))
-    liftIO $ assertBool "Found some actions" (null actionsOrCommands)
+    liftIO $ assertBool "Found some actions (other than \"disable warnings\")"
+      $ all isDisableWarningAction actionsOrCommands
+    where
+      isDisableWarningAction = \case
+        CACodeAction CodeAction{_title} -> "Disable" `T.isPrefixOf` _title && "warnings" `T.isSuffixOf` _title
+        _ -> False
 
   in testGroup "remove redundant function constraints"
   [ check
@@ -4037,7 +4091,10 @@ asyncTests = testGroup "async"
               ]
             void waitForDiagnostics
             actions <- getCodeActions doc (Range (Position 1 0) (Position 1 0))
-            liftIO $ [ _title | CACodeAction CodeAction{_title} <- actions] @=? ["add signature: foo :: a -> a"]
+            liftIO $ [ _title | CACodeAction CodeAction{_title} <- actions] @=?
+              [ "add signature: foo :: a -> a"
+              , "Disable \"missing-signatures\" warnings"
+              ]
     , testSession "request" $ do
             -- Execute a custom request that will block for 1000 seconds
             void $ sendRequest (CustomClientMethod "test") $ BlockSeconds 1000
@@ -4048,7 +4105,10 @@ asyncTests = testGroup "async"
               ]
             void waitForDiagnostics
             actions <- getCodeActions doc (Range (Position 0 0) (Position 0 0))
-            liftIO $ [ _title | CACodeAction CodeAction{_title} <- actions] @=? ["add signature: foo :: a -> a"]
+            liftIO $ [ _title | CACodeAction CodeAction{_title} <- actions] @=?
+              [ "add signature: foo :: a -> a"
+              , "Disable \"missing-signatures\" warnings"
+              ]
     ]
 
 
@@ -4425,3 +4485,9 @@ withTempDir :: (FilePath -> IO a) -> IO a
 withTempDir f = System.IO.Extra.withTempDir $ \dir -> do
   dir' <- canonicalizePath dir
   f dir'
+
+-- | Assert that a value is not 'Nothing', and extract the value.
+assertJust :: MonadIO m => String -> Maybe a -> m a
+assertJust s = \case
+  Nothing -> liftIO $ assertFailure s
+  Just x -> pure x
diff --git a/test/functional/Class.hs b/test/functional/Class.hs
index e02a0440ad..4d02ad4e41 100644
--- a/test/functional/Class.hs
+++ b/test/functional/Class.hs
@@ -32,6 +32,7 @@ tests = testGroup
           @?=
           [ Just "Add placeholders for '=='"
           , Just "Add placeholders for '/='"
+          , Just "Disable \"missing-methods\" warnings"
           ]
   , glodenTest "Creates a placeholder for '=='" "T1" "eq"
     $ \(eqAction:_) -> do
diff --git a/test/functional/FunctionalCodeAction.hs b/test/functional/FunctionalCodeAction.hs
index 5054159396..ed99206f17 100644
--- a/test/functional/FunctionalCodeAction.hs
+++ b/test/functional/FunctionalCodeAction.hs
@@ -367,7 +367,7 @@ redundantImportTests = testGroup "redundant import code actions" [
     , testCase "doesn't touch other imports" $ runSession hlsCommand noLiteralCaps "test/testdata/redundantImportTest/" $ do
         doc <- openDoc "src/MultipleImports.hs" "haskell"
         _   <- waitForDiagnosticsFromSource doc "typecheck"
-        CACommand cmd : _ <- getAllCodeActions doc
+        _ : CACommand cmd : _ <- getAllCodeActions doc
         executeCommand cmd
         contents <- documentContents doc
         liftIO $ T.lines contents @?=