diff --git a/runtime/bin/filter.cc b/runtime/bin/filter.cc
index 6ea6fcdc80a..64420c0d892 100644
--- a/runtime/bin/filter.cc
+++ b/runtime/bin/filter.cc
@@ -347,9 +347,9 @@ intptr_t ZLibDeflateFilter::Processed(uint8_t* buffer,
   switch (deflate(&stream_, end     ? Z_FINISH
                             : flush ? Z_SYNC_FLUSH
                                     : Z_NO_FLUSH)) {
+    case Z_OK:
     case Z_STREAM_END:
-    case Z_BUF_ERROR:
-    case Z_OK: {
+    case Z_BUF_ERROR: {
       intptr_t processed = length - stream_.avail_out;
       if (processed == 0) {
         break;
@@ -413,10 +413,20 @@ intptr_t ZLibInflateFilter::Processed(uint8_t* buffer,
   switch (v = inflate(&stream_, end     ? Z_FINISH
                                 : flush ? Z_SYNC_FLUSH
                                         : Z_NO_FLUSH)) {
+    case Z_OK:
     case Z_STREAM_END:
-    case Z_BUF_ERROR:
-    case Z_OK: {
+    case Z_BUF_ERROR: {
       intptr_t processed = length - stream_.avail_out;
+
+      if (v == Z_STREAM_END) {
+        // Allow for concatenated compressed blocks. For example:
+        // final data = [
+        //  ...gzip.encode([1, 2, 3]),
+        //  ...gzip.encode([4, 5, 6]),
+        // ];
+        // final decoded = gzip.decode(data);  // [1, 2, 3, 4, 5, 6]
+        inflateReset(&stream_);
+      }
       if (processed == 0) {
         break;
       }
diff --git a/tests/standalone/io/zlib_test.dart b/tests/standalone/io/zlib_test.dart
index f3859bf6cce..27c3c7ee1b7 100644
--- a/tests/standalone/io/zlib_test.dart
+++ b/tests/standalone/io/zlib_test.dart
@@ -232,6 +232,24 @@ void testZlibInflateWithLargerWindow() {
   });
 }
 
+void testRoundTripLarge() {
+  for (var gzip in [true, false]) {
+    for (var strategy in [
+      ZLibOption.strategyFiltered,
+      ZLibOption.strategyHuffmanOnly,
+      ZLibOption.strategyRle,
+      ZLibOption.strategyFixed,
+      ZLibOption.strategyDefault,
+    ]) {
+      final uncompressedData = List.generate(2000000, (i) => i % 256);
+      final compressedData =
+          ZLibEncoder(gzip: gzip, strategy: strategy).convert(uncompressedData);
+      final decodedData = new ZLibDecoder().convert(compressedData);
+      Expect.listEquals(uncompressedData, decodedData);
+    }
+  }
+}
+
 void testZlibWithDictionary() {
   var dict = [102, 111, 111, 98, 97, 114];
   var data = [98, 97, 114, 102, 111, 111];
@@ -243,6 +261,39 @@ void testZlibWithDictionary() {
   });
 }
 
+void testConcatenatedBlocks() {
+  for (var gzip in [true, false]) {
+    for (var strategy in [
+      ZLibOption.strategyFiltered,
+      ZLibOption.strategyHuffmanOnly,
+      ZLibOption.strategyRle,
+      ZLibOption.strategyFixed,
+      ZLibOption.strategyDefault,
+    ]) {
+      final compressedData = [
+        ...ZLibEncoder(gzip: gzip, strategy: strategy).convert([1, 2, 3]),
+        ...ZLibEncoder(gzip: gzip, strategy: strategy).convert([4, 5, 6])
+      ];
+      final decodedData = new ZLibDecoder().convert(compressedData);
+      Expect.listEquals([1, 2, 3, 4, 5, 6], decodedData);
+    }
+  }
+}
+
+void testInvalidDataAfterBlock() {
+  for (var gzip in [true, false]) {
+    final compressedData = [
+      ...ZLibEncoder(gzip: gzip).convert([1, 2, 3]),
+      1,
+      2,
+      3
+    ];
+
+    Expect.throwsFormatException(
+        () => new ZLibDecoder().convert(compressedData));
+  }
+}
+
 var generateListTypes = [
   (list) => list,
   (list) => new Uint8List.fromList(list),
@@ -284,6 +335,9 @@ void main() {
   });
   testZlibInflateThrowsWithSmallerWindow();
   testZlibInflateWithLargerWindow();
+  testRoundTripLarge();
   testZlibWithDictionary();
+  testConcatenatedBlocks();
+  testInvalidDataAfterBlock();
   asyncEnd();
 }