diff --git a/src/Monitor/Tracing/Zipkin.hs b/src/Monitor/Tracing/Zipkin.hs
--- a/src/Monitor/Tracing/Zipkin.hs
+++ b/src/Monitor/Tracing/Zipkin.hs
@@ -175,12 +175,13 @@
 addTag key val bldr =
   bldr { builderTags = Map.insert (publicKeyPrefix <> key) (JSON.toJSON val) (builderTags bldr) }
 
--- | Adds a producer kind tag to a builder. This is a convenience method to use with 'rootSpanWith', for example:
+-- | Adds a producer kind tag to a builder. This is a convenience method to use with 'rootSpanWith',
+-- for example:
 --
 -- > rootSpanWith addProducerKind alwaysSampled "root" $ action
 --
--- Use this method if you want to create a root producer span.
--- Otherwise use 'producerSpanWith' to create a sub span with producer kind.
+-- Use this method if you want to create a root producer span. Otherwise use 'producerSpanWith' to
+-- create a sub span with producer kind.
 addProducerKind :: Builder -> Builder
 addProducerKind = addTag kindKey producerKindValue
 
@@ -231,7 +232,7 @@
 b3ToHeaders :: B3 -> Map (CI ByteString) ByteString
 b3ToHeaders (B3 traceID spanID isSampled isDebug mbParentID) =
   let
-    defaultKVs = [(traceIDHeader, encodeTraceID traceID), (spanIDHeader, encodeSpanID spanID)]
+    defaultKVs = [(traceIDHeader, encodeZipkinTraceID traceID), (spanIDHeader, encodeSpanID spanID)]
     parentKVs = (parentSpanIDHeader,) . encodeSpanID <$> maybeToList mbParentID
     sampledKVs = case (isSampled, isDebug) of
       (_, True) -> [(debugHeader, "1")]
@@ -253,7 +254,7 @@
   sampled <- findBool dbg sampledHeader
   guard (not $ sampled == False && dbg)
   B3
-    <$> (find traceIDHeader >>= decodeTraceID)
+    <$> (find traceIDHeader >>= decodeZipkinTraceID)
     <*> (find spanIDHeader >>= decodeSpanID)
     <*> pure sampled
     <*> pure dbg
@@ -268,15 +269,35 @@
       (_ , True) -> "d"
       (True, _) -> "1"
       (False, _) -> "0"
-    required = [encodeTraceID traceID, encodeSpanID spanID, state]
+    required = [encodeZipkinTraceID traceID, encodeSpanID spanID, state]
     optional = encodeSpanID <$> maybeToList mbParentID
   in BS.intercalate "-" $ fmap T.encodeUtf8 $ required ++ optional
 
+-- | Prefix used to fill up 128-bit if only a 64-bit trace identifier is given.
+shortTraceIDPrefix :: Text
+shortTraceIDPrefix = "0000000000000000"
+
+-- | Decodes a zipkin trace ID from a hex-encoded string, returning nothing if it is invalid. Takes
+-- into account that the provided string could be a 16 or 32 lower-hex character trace ID. If the
+-- given string consists of 16 lower-hex characters 'shortTraceIDPrefix' is used to fil up the
+-- 128-bit trace identifier of 'TraceID'.
+decodeZipkinTraceID :: Text -> Maybe TraceID
+decodeZipkinTraceID txt =
+  let normalized = if T.length txt == 16 then shortTraceIDPrefix <> txt else txt
+  in decodeTraceID normalized
+
+-- | Hex-encodes a trace ID, providing a 16 or 32 lower-hex character zipkin trace ID. A 16
+-- lower-hex character string is returned if the first 64-bits of the 'TraceID' are zeros.
+encodeZipkinTraceID :: TraceID -> Text
+encodeZipkinTraceID traceID =
+  let txt = encodeTraceID traceID
+  in fromMaybe txt $ T.stripPrefix shortTraceIDPrefix txt
+
 -- | Deserializes a single header value into a 'B3'.
 b3FromHeaderValue :: ByteString -> Maybe B3
 b3FromHeaderValue bs = case T.splitOn "-" $ T.decodeUtf8 bs of
   (traceIDstr:spanIDstr:strs) -> do
-    traceID <- decodeTraceID traceIDstr
+    traceID <- decodeZipkinTraceID traceIDstr
     spanID <- decodeSpanID spanIDstr
     let buildB3 = B3 traceID spanID
     case strs of
diff --git a/test/Spec.hs b/test/Spec.hs
--- a/test/Spec.hs
+++ b/test/Spec.hs
@@ -71,6 +71,12 @@
         mbBs = ZPK.b3ToHeaderValue <$> ZPK.b3FromHeaderValue bs
       mbBs `shouldBe` Just bs
 
+    it "should round-trip a B3 using a single header with a 16 lower-hex character TraceId" $ do
+      let
+        bs = "64fe8b2a57d3eff7-e457b5a2e4d86bd1-1-05e3ac9a4f6e3b90"
+        mbBs = ZPK.b3ToHeaderValue <$> ZPK.b3FromHeaderValue bs
+      mbBs `shouldBe` Just bs
+
     it "should have equivalent B3 header representations" $ do
       let
         bs = "80f198ee56343ba864fe8b2a57d3eff7-e457b5a2e4d86bd1-1-05e3ac9a4f6e3b90"
diff --git a/tracing.cabal b/tracing.cabal
--- a/tracing.cabal
+++ b/tracing.cabal
@@ -1,7 +1,7 @@
 cabal-version: 2.0
 
 name: tracing
-version: 0.0.7.1
+version: 0.0.7.2
 synopsis: Distributed tracing
 description:
   An OpenTracing-compliant, simple, and extensible distributed tracing library.