diff --git a/src/kits/package/hpkg/PackageFileHeapAccessorBase.cpp b/src/kits/package/hpkg/PackageFileHeapAccessorBase.cpp
index 78461ad94d..024b8f21e9 100644
--- a/src/kits/package/hpkg/PackageFileHeapAccessorBase.cpp
+++ b/src/kits/package/hpkg/PackageFileHeapAccessorBase.cpp
@@ -13,6 +13,7 @@
 #include <algorithm>
 #include <new>
 
+#include <ByteOrder.h>
 #include <package/hpkg/DataOutput.h>
 #include <package/hpkg/ErrorOutput.h>
 
@@ -62,7 +63,7 @@ PackageFileHeapAccessorBase::OffsetArray::InitChunksOffsets(
 
 	uint64 offset = (*this)[baseIndex];
 	for (size_t i = 0; i < chunkCount; i++) {
-		offset += (uint64)chunkSizes[i] + 1;
+		offset += (uint64)B_BENDIAN_TO_HOST_INT16(chunkSizes[i]) + 1;
 			// the stored value is chunkSize - 1
 		size_t index = baseIndex + i + 1;
 			// (baseIndex + i) is the index of the chunk whose size is stored in
diff --git a/src/kits/package/hpkg/PackageFileHeapWriter.cpp b/src/kits/package/hpkg/PackageFileHeapWriter.cpp
index 7bf45fa1b4..d4a12e46e7 100644
--- a/src/kits/package/hpkg/PackageFileHeapWriter.cpp
+++ b/src/kits/package/hpkg/PackageFileHeapWriter.cpp
@@ -11,6 +11,7 @@
 #include <algorithm>
 #include <new>
 
+#include <ByteOrder.h>
 #include <List.h>
 #include <package/hpkg/ErrorOutput.h>
 #include <package/hpkg/HPKGDefs.h>
@@ -439,8 +440,8 @@ PackageFileHeapWriter::Finish()
 
 		for (ssize_t i = 0; i < toWrite; i++, offsetIndex++) {
 			// store chunkSize - 1, so it fits 16 bit (chunks cannot be empty)
-			buffer[i] = uint16(fOffsets[offsetIndex] - fOffsets[offsetIndex - 1]
-				- 1);
+			buffer[i] = B_HOST_TO_BENDIAN_INT16(
+				uint16(fOffsets[offsetIndex] - fOffsets[offsetIndex - 1] - 1));
 		}
 
 		error = _WriteDataUncompressed(buffer, toWrite * 2);