diff --git a/src/OpenFOAM/db/IOstreams/Pstreams/UPstream.H b/src/OpenFOAM/db/IOstreams/Pstreams/UPstream.H
index 81b04bc120bcce1c3cca4da8ce279debb7bc6aef..eb4a485340dde1a8253d0af27aaeada109a362cb 100644
--- a/src/OpenFOAM/db/IOstreams/Pstreams/UPstream.H
+++ b/src/OpenFOAM/db/IOstreams/Pstreams/UPstream.H
@@ -548,9 +548,6 @@ public:
             //  A no-op and returns true if parRun() == false or list is empty
             static bool finishedRequests(UList<UPstream::Request>& requests);
 
-            static int allocateTag(const char* const msg = nullptr);
-            static void freeTag(const int tag, const char* const msg = nullptr);
-
 
         //- Set as parallel run on/off.
         //  \return the previous value
diff --git a/src/Pstream/dummy/UPstream.C b/src/Pstream/dummy/UPstream.C
index 6eddc72490b71b726899cff8d918a7370bff9e9d..2368e9e89946cfa862a37b650efadf214685da28 100644
--- a/src/Pstream/dummy/UPstream.C
+++ b/src/Pstream/dummy/UPstream.C
@@ -87,13 +87,6 @@ void Foam::UPstream::freePstreamCommunicator(const label)
 {}
 
 
-int Foam::UPstream::allocateTag(const char* const msg) { return 0; }
-
-
-void Foam::UPstream::freeTag(const int tag, const char* const msg)
-{}
-
-
 void Foam::UPstream::barrier(const label communicator, UPstream::Request* req)
 {}
 
diff --git a/src/Pstream/mpi/PstreamGlobals.C b/src/Pstream/mpi/PstreamGlobals.C
index de5634b906963b6ca52ec3198c410b8a6377bf64..601d371331d838f91e088ee515ca26bd91689afc 100644
--- a/src/Pstream/mpi/PstreamGlobals.C
+++ b/src/Pstream/mpi/PstreamGlobals.C
@@ -38,9 +38,6 @@ Foam::DynamicList<MPI_Group> Foam::PstreamGlobals::MPIGroups_;
 Foam::DynamicList<MPI_Request> Foam::PstreamGlobals::outstandingRequests_;
 Foam::DynamicList<Foam::label> Foam::PstreamGlobals::freedRequests_;
 
-int Foam::PstreamGlobals::nTags_ = 0;
-Foam::DynamicList<int> Foam::PstreamGlobals::freedTags_;
-
 
 // * * * * * * * * * * * * * * * Global Functions  * * * * * * * * * * * * * //
 
diff --git a/src/Pstream/mpi/PstreamGlobals.H b/src/Pstream/mpi/PstreamGlobals.H
index a45bd1b858d2e9f7d8ae10c802a0d4174cdbad3a..1edb623a1a0460dd6df39ed30d3d1b31cf0fd7d7 100644
--- a/src/Pstream/mpi/PstreamGlobals.H
+++ b/src/Pstream/mpi/PstreamGlobals.H
@@ -73,12 +73,6 @@ extern DynamicList<MPI_Group> MPIGroups_;
 extern DynamicList<MPI_Request> outstandingRequests_;
 extern DynamicList<label> freedRequests_;
 
-//- Max outstanding message tag operations.
-extern int nTags_;
-
-//- Free'd message tags
-extern DynamicList<int> freedTags_;
-
 
 // * * * * * * * * * * * * * * * Global Functions  * * * * * * * * * * * * * //
 
diff --git a/src/Pstream/mpi/UPstream.C b/src/Pstream/mpi/UPstream.C
index a84cdddf82aaabb34510e87f461d21b587e6310c..bbd879d806eb9920e6ce63f5653798a47fd697c3 100644
--- a/src/Pstream/mpi/UPstream.C
+++ b/src/Pstream/mpi/UPstream.C
@@ -713,42 +713,6 @@ void Foam::UPstream::freePstreamCommunicator(const label index)
 }
 
 
-int Foam::UPstream::allocateTag(const char* const msg)
-{
-    int tag;
-    if (PstreamGlobals::freedTags_.size())
-    {
-        tag = PstreamGlobals::freedTags_.back();
-        PstreamGlobals::freedTags_.pop_back();
-    }
-    else
-    {
-        tag = ++PstreamGlobals::nTags_;
-    }
-
-    if (debug)
-    {
-        Pout<< "UPstream::allocateTag";
-        if (msg) Pout<< ' ' << msg;
-        Pout<< " : tag:" << tag << endl;
-    }
-
-    return tag;
-}
-
-
-void Foam::UPstream::freeTag(const int tag, const char* const msg)
-{
-    if (debug)
-    {
-        Pout<< "UPstream::freeTag ";
-        if (msg) Pout<< ' ' << msg;
-        Pout<< " : tag:" << tag << endl;
-    }
-    PstreamGlobals::freedTags_.push_back(tag);
-}
-
-
 void Foam::UPstream::barrier(const label communicator, UPstream::Request* req)
 {
     // No-op for non-parallel