diff --git a/hledger-ui/hledger-ui.cabal b/hledger-ui/hledger-ui.cabal
index d689949b4c3..809ee425ad7 100644
--- a/hledger-ui/hledger-ui.cabal
+++ b/hledger-ui/hledger-ui.cabal
@@ -119,4 +119,4 @@ executable hledger-ui
     , hledger-ui
   default-language: Haskell2010
   if flag(threaded)
-    ghc-options: -threaded
+    ghc-options: -threaded -with-rtsopts=-T
diff --git a/hledger-web/hledger-web.cabal b/hledger-web/hledger-web.cabal
index 49763925ed8..ec1c91572e8 100644
--- a/hledger-web/hledger-web.cabal
+++ b/hledger-web/hledger-web.cabal
@@ -225,7 +225,7 @@ executable hledger-web
   if flag(library-only)
     buildable: False
   if flag(threaded)
-    ghc-options: -threaded
+    ghc-options: -threaded -with-rtsopts=-T
 
 test-suite test
   type: exitcode-stdio-1.0
diff --git a/hledger/hledger.cabal b/hledger/hledger.cabal
index ad54658335a..3b64b252a7a 100644
--- a/hledger/hledger.cabal
+++ b/hledger/hledger.cabal
@@ -231,7 +231,7 @@ executable hledger
     build-depends:
         terminfo
   if flag(threaded)
-    ghc-options: -threaded
+    ghc-options: -threaded -with-rtsopts=-T
 
 test-suite unittest
   type: exitcode-stdio-1.0