diff --git a/crypto_stream.go b/crypto_stream.go
index b9263da6..c98bc6d4 100644
--- a/crypto_stream.go
+++ b/crypto_stream.go
@@ -19,7 +19,7 @@ type cryptoStreamI interface {
 	// methods needed for flow control
 	GetWindowUpdate() protocol.ByteCount
 	HandleMaxStreamDataFrame(*wire.MaxStreamDataFrame)
-	IsFlowControlBlocked() bool
+	IsFlowControlBlocked() (bool, protocol.ByteCount)
 }
 
 type cryptoStream struct {
diff --git a/internal/flowcontrol/base_flow_controller.go b/internal/flowcontrol/base_flow_controller.go
index f7d70c7e..616e4bf5 100644
--- a/internal/flowcontrol/base_flow_controller.go
+++ b/internal/flowcontrol/base_flow_controller.go
@@ -79,11 +79,16 @@ func (c *baseFlowController) getWindowUpdate() protocol.ByteCount {
 	return c.receiveWindow
 }
 
-func (c *baseFlowController) IsBlocked() bool {
+// IsBlocked says if it is blocked by flow control.
+// If it is blocked, the offset is returned.
+func (c *baseFlowController) IsBlocked() (bool, protocol.ByteCount) {
 	c.mutex.RLock()
 	defer c.mutex.RUnlock()
 
-	return c.sendWindowSize() == 0
+	if c.sendWindowSize() != 0 {
+		return false, 0
+	}
+	return true, c.sendWindow
 }
 
 // maybeAdjustWindowIncrement increases the receiveWindowIncrement if we're sending updates too often.
diff --git a/internal/flowcontrol/base_flow_controller_test.go b/internal/flowcontrol/base_flow_controller_test.go
index 9239722c..790d31f3 100644
--- a/internal/flowcontrol/base_flow_controller_test.go
+++ b/internal/flowcontrol/base_flow_controller_test.go
@@ -54,7 +54,9 @@ var _ = Describe("Base Flow controller", func() {
 			controller.UpdateSendWindow(100)
 			Expect(controller.IsBlocked()).To(BeFalse())
 			controller.AddBytesSent(100)
-			Expect(controller.IsBlocked()).To(BeTrue())
+			blocked, offset := controller.IsBlocked()
+			Expect(blocked).To(BeTrue())
+			Expect(offset).To(Equal(protocol.ByteCount(100)))
 		})
 	})
 
diff --git a/internal/flowcontrol/interface.go b/internal/flowcontrol/interface.go
index 75ec6fac..f5577283 100644
--- a/internal/flowcontrol/interface.go
+++ b/internal/flowcontrol/interface.go
@@ -5,7 +5,7 @@ import "github.com/lucas-clemente/quic-go/internal/protocol"
 type flowController interface {
 	// for sending
 	SendWindowSize() protocol.ByteCount
-	IsBlocked() bool
+	IsBlocked() (bool, protocol.ByteCount)
 	UpdateSendWindow(protocol.ByteCount)
 	AddBytesSent(protocol.ByteCount)
 	// for receiving
diff --git a/internal/flowcontrol/stream_flow_controller_test.go b/internal/flowcontrol/stream_flow_controller_test.go
index ed51adcf..5938e5e6 100644
--- a/internal/flowcontrol/stream_flow_controller_test.go
+++ b/internal/flowcontrol/stream_flow_controller_test.go
@@ -233,7 +233,8 @@ var _ = Describe("Stream Flow controller", func() {
 			controller.connection.UpdateSendWindow(50)
 			controller.UpdateSendWindow(100)
 			controller.AddBytesSent(50)
-			Expect(controller.connection.IsBlocked()).To(BeTrue())
+			blocked, _ := controller.connection.IsBlocked()
+			Expect(blocked).To(BeTrue())
 			Expect(controller.IsBlocked()).To(BeFalse())
 		})
 	})
diff --git a/internal/mocks/connection_flow_controller.go b/internal/mocks/connection_flow_controller.go
index 26c77cbe..cf99e9d1 100644
--- a/internal/mocks/connection_flow_controller.go
+++ b/internal/mocks/connection_flow_controller.go
@@ -66,10 +66,11 @@ func (_mr *MockConnectionFlowControllerMockRecorder) GetWindowUpdate() *gomock.C
 }
 
 // IsBlocked mocks base method
-func (_m *MockConnectionFlowController) IsBlocked() bool {
+func (_m *MockConnectionFlowController) IsBlocked() (bool, protocol.ByteCount) {
 	ret := _m.ctrl.Call(_m, "IsBlocked")
 	ret0, _ := ret[0].(bool)
-	return ret0
+	ret1, _ := ret[1].(protocol.ByteCount)
+	return ret0, ret1
 }
 
 // IsBlocked indicates an expected call of IsBlocked
diff --git a/internal/mocks/stream.go b/internal/mocks/stream.go
index 107d9177..0500861b 100644
--- a/internal/mocks/stream.go
+++ b/internal/mocks/stream.go
@@ -129,10 +129,11 @@ func (_mr *MockStreamIMockRecorder) HandleStreamFrame(arg0 interface{}) *gomock.
 }
 
 // IsFlowControlBlocked mocks base method
-func (_m *MockStreamI) IsFlowControlBlocked() bool {
+func (_m *MockStreamI) IsFlowControlBlocked() (bool, protocol.ByteCount) {
 	ret := _m.ctrl.Call(_m, "IsFlowControlBlocked")
 	ret0, _ := ret[0].(bool)
-	return ret0
+	ret1, _ := ret[1].(protocol.ByteCount)
+	return ret0, ret1
 }
 
 // IsFlowControlBlocked indicates an expected call of IsFlowControlBlocked
diff --git a/internal/mocks/stream_flow_controller.go b/internal/mocks/stream_flow_controller.go
index 7e970bb4..8bca7b9e 100644
--- a/internal/mocks/stream_flow_controller.go
+++ b/internal/mocks/stream_flow_controller.go
@@ -66,10 +66,11 @@ func (_mr *MockStreamFlowControllerMockRecorder) GetWindowUpdate() *gomock.Call
 }
 
 // IsBlocked mocks base method
-func (_m *MockStreamFlowController) IsBlocked() bool {
+func (_m *MockStreamFlowController) IsBlocked() (bool, protocol.ByteCount) {
 	ret := _m.ctrl.Call(_m, "IsBlocked")
 	ret0, _ := ret[0].(bool)
-	return ret0
+	ret1, _ := ret[1].(protocol.ByteCount)
+	return ret0, ret1
 }
 
 // IsBlocked indicates an expected call of IsBlocked
diff --git a/stream.go b/stream.go
index 6dacfd3f..aacacd77 100644
--- a/stream.go
+++ b/stream.go
@@ -25,7 +25,7 @@ type streamI interface {
 	// methods needed for flow control
 	GetWindowUpdate() protocol.ByteCount
 	HandleMaxStreamDataFrame(*wire.MaxStreamDataFrame)
-	IsFlowControlBlocked() bool
+	IsFlowControlBlocked() (bool, protocol.ByteCount)
 }
 
 // A Stream assembles the data from StreamFrames and provides a super-convenient Read-Interface
@@ -484,7 +484,7 @@ func (s *stream) HandleMaxStreamDataFrame(frame *wire.MaxStreamDataFrame) {
 	s.flowController.UpdateSendWindow(frame.ByteOffset)
 }
 
-func (s *stream) IsFlowControlBlocked() bool {
+func (s *stream) IsFlowControlBlocked() (bool, protocol.ByteCount) {
 	return s.flowController.IsBlocked()
 }
 
diff --git a/stream_framer.go b/stream_framer.go
index 9244bc3e..d5fa09a7 100644
--- a/stream_framer.go
+++ b/stream_framer.go
@@ -105,11 +105,16 @@ func (f *streamFramer) maybePopNormalFrames(maxTotalLen protocol.ByteCount) (res
 		}
 
 		// Finally, check if we are now FC blocked and should queue a BLOCKED frame
-		if !frame.FinBit && s.IsFlowControlBlocked() {
-			f.blockedFrameQueue = append(f.blockedFrameQueue, &wire.StreamBlockedFrame{StreamID: s.StreamID()})
+		if !frame.FinBit {
+			if blocked, offset := s.IsFlowControlBlocked(); blocked {
+				f.blockedFrameQueue = append(f.blockedFrameQueue, &wire.StreamBlockedFrame{
+					StreamID: s.StreamID(),
+					Offset:   offset,
+				})
+			}
 		}
-		if f.connFlowController.IsBlocked() {
-			f.blockedFrameQueue = append(f.blockedFrameQueue, &wire.BlockedFrame{})
+		if blocked, offset := f.connFlowController.IsBlocked(); blocked {
+			f.blockedFrameQueue = append(f.blockedFrameQueue, &wire.BlockedFrame{Offset: offset})
 		}
 
 		res = append(res, frame)
diff --git a/stream_framer_test.go b/stream_framer_test.go
index cb5ba7c3..d3307cdd 100644
--- a/stream_framer_test.go
+++ b/stream_framer_test.go
@@ -72,8 +72,8 @@ var _ = Describe("Stream Framer", func() {
 		BeforeEach(func() {
 			// nothing is blocked here
 			connFC.EXPECT().IsBlocked().AnyTimes()
-			stream1.EXPECT().IsFlowControlBlocked().Return(false).AnyTimes()
-			stream2.EXPECT().IsFlowControlBlocked().Return(false).AnyTimes()
+			stream1.EXPECT().IsFlowControlBlocked().Return(false, protocol.ByteCount(0)).AnyTimes()
+			stream2.EXPECT().IsFlowControlBlocked().Return(false, protocol.ByteCount(0)).AnyTimes()
 		})
 
 		It("returns nil when popping an empty framer", func() {
@@ -272,13 +272,13 @@ var _ = Describe("Stream Framer", func() {
 				StreamID: id1,
 				Data:     []byte("foobar"),
 			})
-			stream1.EXPECT().IsFlowControlBlocked().Return(true)
+			stream1.EXPECT().IsFlowControlBlocked().Return(true, protocol.ByteCount(0x1234))
 			frames := framer.PopStreamFrames(1000)
 			Expect(frames).To(HaveLen(1))
-			f := framer.PopBlockedFrame()
-			Expect(f).To(BeAssignableToTypeOf(&wire.StreamBlockedFrame{}))
-			bf := f.(*wire.StreamBlockedFrame)
-			Expect(bf.StreamID).To(Equal(stream1.StreamID()))
+			Expect(framer.PopBlockedFrame()).To(Equal(&wire.StreamBlockedFrame{
+				StreamID: stream1.StreamID(),
+				Offset:   0x1234,
+			}))
 			Expect(framer.PopBlockedFrame()).To(BeNil())
 		})
 
@@ -300,15 +300,14 @@ var _ = Describe("Stream Framer", func() {
 
 		It("queues and pops BLOCKED frames for connection blocked streams", func() {
 			setNoData(stream2)
-			connFC.EXPECT().IsBlocked().Return(true)
+			connFC.EXPECT().IsBlocked().Return(true, protocol.ByteCount(0x4321))
 			stream1.EXPECT().PopStreamFrame(gomock.Any()).Return(&wire.StreamFrame{
 				StreamID: id1,
 				Data:     []byte("foo"),
 			})
-			stream1.EXPECT().IsFlowControlBlocked().Return(false)
+			stream1.EXPECT().IsFlowControlBlocked().Return(false, protocol.ByteCount(0))
 			framer.PopStreamFrames(1000)
-			f := framer.PopBlockedFrame()
-			Expect(f).To(BeAssignableToTypeOf(&wire.BlockedFrame{}))
+			Expect(framer.PopBlockedFrame()).To(Equal(&wire.BlockedFrame{Offset: 0x4321}))
 			Expect(framer.PopBlockedFrame()).To(BeNil())
 		})
 	})
diff --git a/stream_test.go b/stream_test.go
index 5bc197cb..b9ce75e0 100644
--- a/stream_test.go
+++ b/stream_test.go
@@ -1146,10 +1146,13 @@ var _ = Describe("Stream", func() {
 
 	Context("flow control", func() {
 		It("says when it's flow control blocked", func() {
-			mockFC.EXPECT().IsBlocked().Return(false)
-			Expect(str.IsFlowControlBlocked()).To(BeFalse())
-			mockFC.EXPECT().IsBlocked().Return(true)
-			Expect(str.IsFlowControlBlocked()).To(BeTrue())
+			mockFC.EXPECT().IsBlocked().Return(false, protocol.ByteCount(0))
+			blocked, _ := str.IsFlowControlBlocked()
+			Expect(blocked).To(BeFalse())
+			mockFC.EXPECT().IsBlocked().Return(true, protocol.ByteCount(0x1337))
+			blocked, offset := str.IsFlowControlBlocked()
+			Expect(blocked).To(BeTrue())
+			Expect(offset).To(Equal(protocol.ByteCount(0x1337)))
 		})
 
 		It("updates the flow control window", func() {