diff --git a/rtpcodec.go b/rtpcodec.go
index d4733dbd07e..d03dba0bd30 100644
--- a/rtpcodec.go
+++ b/rtpcodec.go
@@ -5,6 +5,7 @@ package webrtc
 
 import (
 	"fmt"
+	"strconv"
 	"strings"
 
 	"github.com/pion/webrtc/v4/internal/fmtp"
@@ -155,6 +156,38 @@ func findRTXPayloadType(needle PayloadType, haystack []RTPCodecParameters) Paylo
 	return PayloadType(0)
 }
 
+// Given needle CodecParameters, returns if needle is RTX and
+// if primary codec corresponding to that needle is in the haystack of codecs.
+func primaryPayloadTypeForRTXExists(needle RTPCodecParameters, haystack []RTPCodecParameters) (
+	isRTX bool, primaryExists bool,
+) {
+	if !strings.EqualFold(needle.MimeType, MimeTypeRTX) {
+		return
+	}
+
+	isRTX = true
+	parsed := fmtp.Parse(needle.MimeType, needle.ClockRate, needle.Channels, needle.SDPFmtpLine)
+	aptPayload, ok := parsed.Parameter("apt")
+	if !ok {
+		return
+	}
+
+	primaryPayloadType, err := strconv.Atoi(aptPayload)
+	if err != nil || primaryPayloadType < 0 || primaryPayloadType > 255 {
+		return
+	}
+
+	for _, c := range haystack {
+		if c.PayloadType == PayloadType(primaryPayloadType) {
+			primaryExists = true
+
+			return
+		}
+	}
+
+	return
+}
+
 // For now, only FlexFEC is supported.
 func findFECPayloadType(haystack []RTPCodecParameters) PayloadType {
 	for _, c := range haystack {
diff --git a/rtpcodec_test.go b/rtpcodec_test.go
index 0328f36f7f2..8b5923decfc 100644
--- a/rtpcodec_test.go
+++ b/rtpcodec_test.go
@@ -9,6 +9,199 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
+func TestFindPrimaryPayloadTypeForRTX(t *testing.T) {
+	for _, test := range []struct {
+		Name                string
+		Needle              RTPCodecParameters
+		Haystack            []RTPCodecParameters
+		ResultIsRTX         bool
+		ResultPrimaryExists bool
+	}{
+		{
+			Name: "not RTX",
+			Needle: RTPCodecParameters{
+				PayloadType: 2,
+				RTPCodecCapability: RTPCodecCapability{
+					MimeType:    MimeTypeH264,
+					ClockRate:   90000,
+					SDPFmtpLine: "apt=2",
+				},
+			},
+			Haystack: []RTPCodecParameters{
+				{
+					PayloadType: 1,
+					RTPCodecCapability: RTPCodecCapability{
+						MimeType:  MimeTypeH264,
+						ClockRate: 90000,
+					},
+				},
+			},
+			ResultIsRTX:         false,
+			ResultPrimaryExists: false,
+		},
+		{
+			Name: "incorrect fmtp",
+			Needle: RTPCodecParameters{
+				PayloadType: 2,
+				RTPCodecCapability: RTPCodecCapability{
+					MimeType:    MimeTypeRTX,
+					ClockRate:   90000,
+					SDPFmtpLine: "incorrect-fmtp",
+				},
+			},
+			Haystack: []RTPCodecParameters{
+				{
+					PayloadType: 1,
+					RTPCodecCapability: RTPCodecCapability{
+						MimeType:  MimeTypeH264,
+						ClockRate: 90000,
+					},
+				},
+			},
+			ResultIsRTX:         true,
+			ResultPrimaryExists: false,
+		},
+		{
+			Name: "incomplete fmtp",
+			Needle: RTPCodecParameters{
+				PayloadType: 2,
+				RTPCodecCapability: RTPCodecCapability{
+					MimeType:    MimeTypeRTX,
+					ClockRate:   90000,
+					SDPFmtpLine: "apt=",
+				},
+			},
+			Haystack: []RTPCodecParameters{
+				{
+					PayloadType: 1,
+					RTPCodecCapability: RTPCodecCapability{
+						MimeType:  MimeTypeH264,
+						ClockRate: 90000,
+					},
+				},
+			},
+			ResultIsRTX:         true,
+			ResultPrimaryExists: false,
+		},
+		{
+			Name: "primary payload type outside range (negative)",
+			Needle: RTPCodecParameters{
+				PayloadType: 2,
+				RTPCodecCapability: RTPCodecCapability{
+					MimeType:    MimeTypeRTX,
+					ClockRate:   90000,
+					SDPFmtpLine: "apt=-10",
+				},
+			},
+			Haystack: []RTPCodecParameters{
+				{
+					PayloadType: 1,
+					RTPCodecCapability: RTPCodecCapability{
+						MimeType:  MimeTypeH264,
+						ClockRate: 90000,
+					},
+				},
+			},
+			ResultIsRTX:         true,
+			ResultPrimaryExists: false,
+		},
+		{
+			Name: "primary payload type outside range (high positive)",
+			Needle: RTPCodecParameters{
+				PayloadType: 2,
+				RTPCodecCapability: RTPCodecCapability{
+					MimeType:    MimeTypeRTX,
+					ClockRate:   90000,
+					SDPFmtpLine: "apt=1000",
+				},
+			},
+			Haystack: []RTPCodecParameters{
+				{
+					PayloadType: 1,
+					RTPCodecCapability: RTPCodecCapability{
+						MimeType:  MimeTypeH264,
+						ClockRate: 90000,
+					},
+				},
+			},
+			ResultIsRTX:         true,
+			ResultPrimaryExists: false,
+		},
+		{
+			Name: "non-matching needle",
+			Needle: RTPCodecParameters{
+				PayloadType: 2,
+				RTPCodecCapability: RTPCodecCapability{
+					MimeType:    MimeTypeRTX,
+					ClockRate:   90000,
+					SDPFmtpLine: "apt=23",
+				},
+			},
+			Haystack: []RTPCodecParameters{
+				{
+					PayloadType: 1,
+					RTPCodecCapability: RTPCodecCapability{
+						MimeType:  MimeTypeH264,
+						ClockRate: 90000,
+					},
+				},
+			},
+			ResultIsRTX:         true,
+			ResultPrimaryExists: false,
+		},
+		{
+			Name: "matching needle",
+			Needle: RTPCodecParameters{
+				PayloadType: 2,
+				RTPCodecCapability: RTPCodecCapability{
+					MimeType:    MimeTypeRTX,
+					ClockRate:   90000,
+					SDPFmtpLine: "apt=1",
+				},
+			},
+			Haystack: []RTPCodecParameters{
+				{
+					PayloadType: 1,
+					RTPCodecCapability: RTPCodecCapability{
+						MimeType:  MimeTypeH264,
+						ClockRate: 90000,
+					},
+				},
+			},
+			ResultIsRTX:         true,
+			ResultPrimaryExists: true,
+		},
+		{
+			Name: "matching fmtp is a substring",
+			Needle: RTPCodecParameters{
+				PayloadType: 2,
+				RTPCodecCapability: RTPCodecCapability{
+					MimeType:    MimeTypeRTX,
+					ClockRate:   90000,
+					SDPFmtpLine: "apt=1;rtx-time:2000",
+				},
+			},
+			Haystack: []RTPCodecParameters{
+				{
+					PayloadType: 1,
+					RTPCodecCapability: RTPCodecCapability{
+						MimeType:  MimeTypeH264,
+						ClockRate: 90000,
+					},
+				},
+			},
+			ResultIsRTX:         true,
+			ResultPrimaryExists: true,
+		},
+	} {
+		t.Run(test.Name, func(t *testing.T) {
+			isRTX, primaryExists := primaryPayloadTypeForRTXExists(test.Needle, test.Haystack)
+			assert.Equal(t, test.ResultIsRTX, isRTX)
+			assert.Equal(t, test.ResultPrimaryExists, primaryExists)
+		})
+	}
+}
+
 func TestFindFECPayloadType(t *testing.T) {
 	for _, test := range []struct {
 		Haystack          []RTPCodecParameters
diff --git a/rtptransceiver.go b/rtptransceiver.go
index 5ce0f2d4819..3741e932ff8 100644
--- a/rtptransceiver.go
+++ b/rtptransceiver.go
@@ -8,6 +8,7 @@ package webrtc
 
 import (
 	"fmt"
+	"strings"
 	"sync"
 	"sync/atomic"
 
@@ -60,6 +61,19 @@ func (t *RTPTransceiver) SetCodecPreferences(codecs []RTPCodecParameters) error
 		}
 	}
 
+	// remove RTX codecs if there is no corresponding primary codec
+	for i := len(codecs) - 1; i >= 0; i-- {
+		c := codecs[i]
+		if !strings.EqualFold(c.MimeType, MimeTypeRTX) {
+			continue
+		}
+
+		if isRTX, primaryExists := primaryPayloadTypeForRTXExists(c, codecs); isRTX && !primaryExists {
+			// no primary for RTX, remove the RTX
+			codecs = append(codecs[:i], codecs[i+1:]...)
+		}
+	}
+
 	t.codecs = codecs
 
 	return nil