diff --git a/CHANGELOG.md b/CHANGELOG.md
index 52d6108713e8..aca054ac7f04 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -34,6 +34,7 @@
 - [[PR 1004]](https://github.com/parthenon-hpc-lab/parthenon/pull/1004) Allow parameter modification from an input file for restarts
 
 ### Fixed (not changing behavior/API/variables/...)
+- [[PR 1146]](https://github.com/parthenon-hpc-lab/parthenon/pull/1146) Fix an issue outputting >4GB single variables per rank
 - [[PR 1144]](https://github.com/parthenon-hpc-lab/parthenon/pull/1144) Fix some restarts w/non-CC fields
 - [[PR 1132]](https://github.com/parthenon-hpc-lab/parthenon/pull/1132) Fix regional dependencies for iterative task lists and make solvers work for arbirtrary MeshData partitioning
 - [[PR 1139]](https://github.com/parthenon-hpc-lab/parthenon/pull/1139) only add --expt-relaxed-constexpr for COMPILE_LANGUAGE:CXX
diff --git a/src/outputs/parthenon_hdf5.cpp b/src/outputs/parthenon_hdf5.cpp
index 8ce995ebd748..7872e2ad4d03 100644
--- a/src/outputs/parthenon_hdf5.cpp
+++ b/src/outputs/parthenon_hdf5.cpp
@@ -76,8 +76,8 @@ void PHDF5Output::WriteOutputFileImpl(Mesh *pm, ParameterInput *pin, SimTime *tm
   // HDF5 structures
   // Also writes companion xdmf file
 
-  const int max_blocks_global = pm->nbtotal;
-  const int num_blocks_local = static_cast<int>(pm->block_list.size());
+  const size_t max_blocks_global = pm->nbtotal;
+  const size_t num_blocks_local = pm->block_list.size();
 
   const IndexDomain theDomain =
       (output_params.include_ghost_zones ? IndexDomain::entire : IndexDomain::interior);
@@ -301,9 +301,9 @@ void PHDF5Output::WriteOutputFileImpl(Mesh *pm, ParameterInput *pin, SimTime *tm
   std::vector<int> sparse_dealloc_count(num_blocks_local * num_sparse);
 
   // allocate space for largest size variable
-  int varSize_max = 0;
+  size_t varSize_max = 0;
   for (auto &vinfo : all_vars_info) {
-    const int varSize = vinfo.Size();
+    const size_t varSize = vinfo.Size();
     varSize_max = std::max(varSize_max, varSize);
   }