diff --git a/contrib/gitian-descriptors/gitian-linux.yml b/contrib/gitian-descriptors/gitian-linux.yml
--- a/contrib/gitian-descriptors/gitian-linux.yml
+++ b/contrib/gitian-descriptors/gitian-linux.yml
@@ -66,8 +66,6 @@
 
   export QT_RCC_TEST=1
   export QT_RCC_SOURCE_DATE_OVERRIDE=1
-  export GZIP="-9n"
-  export TAR_OPTIONS="--mtime="$REFERENCE_DATE\\\ $REFERENCE_TIME""
   export TZ="UTC"
   export BUILD_DIR=`pwd`
   mkdir -p ${WRAP_DIR}
@@ -144,8 +142,8 @@
   # Correct tar file order
   mkdir -p temp
   pushd temp
-  tar xf ../$SOURCEDIST
-  find bitcoin-abc-* | sort | tar --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ../$SOURCEDIST
+  tar -xf ../$SOURCEDIST
+  find bitcoin-abc-* | sort | tar --mtime="${REFERENCE_DATETIME}" --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ../$SOURCEDIST
   popd
 
   ORIGPATH="$PATH"
@@ -177,8 +175,8 @@
     ninja install-debug
 
     cd installed
-    find ${DISTNAME} -not -name "*.dbg" | sort | tar --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ${OUTDIR}/${DISTNAME}-${i}.tar.gz
-    find ${DISTNAME} -name "*.dbg" | sort | tar --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ${OUTDIR}/${DISTNAME}-${i}-debug.tar.gz
+    find ${DISTNAME} -not -name "*.dbg" | sort | tar --mtime="${REFERENCE_DATETIME}" --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ${OUTDIR}/${DISTNAME}-${i}.tar.gz
+    find ${DISTNAME} -name "*.dbg" | sort | tar --mtime="${REFERENCE_DATETIME}" --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ${OUTDIR}/${DISTNAME}-${i}-debug.tar.gz
     cd ../../
     rm -rf distsrc-${i}
   done
diff --git a/contrib/gitian-descriptors/gitian-osx.yml b/contrib/gitian-descriptors/gitian-osx.yml
--- a/contrib/gitian-descriptors/gitian-osx.yml
+++ b/contrib/gitian-descriptors/gitian-osx.yml
@@ -58,8 +58,6 @@
 
   export QT_RCC_TEST=1
   export QT_RCC_SOURCE_DATE_OVERRIDE=1
-  export GZIP="-9n"
-  export TAR_OPTIONS="--mtime="$REFERENCE_DATE\\\ $REFERENCE_TIME""
   export TZ="UTC"
   export BUILD_DIR=`pwd`
   mkdir -p ${WRAP_DIR}
@@ -144,8 +142,8 @@
   # Correct tar file order
   mkdir -p temp
   pushd temp
-  tar xf ../$SOURCEDIST
-  find bitcoin-abc-* | sort | tar --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ../$SOURCEDIST
+  tar -xf ../$SOURCEDIST
+  find bitcoin-abc-* | sort | tar --mtime="${REFERENCE_DATETIME}" --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ../$SOURCEDIST
   popd
 
   ORIGPATH="$PATH"
@@ -184,7 +182,7 @@
     cp ${BASEPREFIX}/${i}/native/bin/${i}-pagestuff unsigned-app-${i}/pagestuff
     mv dist unsigned-app-${i}
     pushd unsigned-app-${i}
-    find . | sort | tar --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ${OUTDIR}/${DISTNAME}-osx-unsigned.tar.gz
+    find . | sort | tar --mtime="${REFERENCE_DATETIME}" --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ${OUTDIR}/${DISTNAME}-osx-unsigned.tar.gz
     popd
 
     ninja osx-dmg
@@ -192,7 +190,7 @@
 
     cd installed
     find -path "*.app*" -type f -executable -exec mv {} ${DISTNAME}/bin/bitcoin-qt \;
-    find ${DISTNAME} -not -path "*.app*" | sort | tar --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ${OUTDIR}/${DISTNAME}-${i}.tar.gz
+    find ${DISTNAME} -not -path "*.app*" | sort | tar --mtime="${REFERENCE_DATETIME}" --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ${OUTDIR}/${DISTNAME}-${i}.tar.gz
     cd ../../
   done
   mkdir -p $OUTDIR/src
diff --git a/contrib/gitian-descriptors/gitian-win.yml b/contrib/gitian-descriptors/gitian-win.yml
--- a/contrib/gitian-descriptors/gitian-win.yml
+++ b/contrib/gitian-descriptors/gitian-win.yml
@@ -53,8 +53,6 @@
 
   export QT_RCC_TEST=1
   export QT_RCC_SOURCE_DATE_OVERRIDE=1
-  export GZIP="-9n"
-  export TAR_OPTIONS="--mtime="$REFERENCE_DATE\\\ $REFERENCE_TIME""
   export TZ="UTC"
   export BUILD_DIR=`pwd`
   mkdir -p ${WRAP_DIR}
@@ -158,8 +156,8 @@
   # Correct tar file order
   mkdir -p temp
   pushd temp
-  tar xf ../$SOURCEDIST
-  find bitcoin-abc-* | sort | tar --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ../$SOURCEDIST
+  tar -xf ../$SOURCEDIST
+  find bitcoin-abc-* | sort | tar --mtime="${REFERENCE_DATETIME}" --no-recursion --mode='u+rw,go+r-w,a+X' --owner=0 --group=0 -c -T - | gzip -9n > ../$SOURCEDIST
   mkdir -p $OUTDIR/src
   cp ../$SOURCEDIST $OUTDIR/src
   popd