diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,3 +1,7 @@
+## 2.1.5
+
+* Allow timestamp value in database to be serialized (presumes UTC timezone) [Yesod #391](https://github.com/yesodweb/persistent/issues/391)
+
 ## 2.1.4
 
 * Treat unknown extension types as PersistDbSpecific values [#385](https://github.com/yesodweb/persistent/pull/385)
diff --git a/Database/Persist/Postgresql.hs b/Database/Persist/Postgresql.hs
--- a/Database/Persist/Postgresql.hs
+++ b/Database/Persist/Postgresql.hs
@@ -65,6 +65,8 @@
 import System.Environment (getEnvironment)
 import Data.Int (Int64)
 import Data.Monoid ((<>))
+import Data.Time (utc, localTimeToUTC)
+
 -- | A @libpq@ connection string.  A simple example of connection
 -- string would be @\"host=localhost port=5432 user=test
 -- dbname=test password=test\"@.  Please read libpq's
@@ -314,7 +316,7 @@
     , (k PS.varchar,     convertPV PersistText)
     , (k PS.date,        convertPV PersistDay)
     , (k PS.time,        convertPV PersistTimeOfDay)
-    , (k PS.timestamp,   convertPV PersistUTCTime)
+    , (k PS.timestamp,   convertPV (PersistUTCTime. localTimeToUTC utc))
     , (k PS.timestamptz, convertPV PersistUTCTime)
     , (k PS.bit,         convertPV PersistInt64)
     , (k PS.varbit,      convertPV PersistInt64)
diff --git a/persistent-postgresql.cabal b/persistent-postgresql.cabal
--- a/persistent-postgresql.cabal
+++ b/persistent-postgresql.cabal
@@ -1,5 +1,5 @@
 name:            persistent-postgresql
-version:         2.1.4
+version:         2.1.5
 license:         MIT
 license-file:    LICENSE
 author:          Felipe Lessa, Michael Snoyman <michael@snoyman.com>