diff --git a/extended_query_builder.go b/extended_query_builder.go
index 0cf3d28c8..526b0e953 100644
--- a/extended_query_builder.go
+++ b/extended_query_builder.go
@@ -3,7 +3,6 @@ package pgx
 import (
 	"fmt"
 
-	"github.com/jackc/pgx/v5/internal/anynil"
 	"github.com/jackc/pgx/v5/pgconn"
 	"github.com/jackc/pgx/v5/pgtype"
 )
@@ -117,10 +116,6 @@ func (eqb *ExtendedQueryBuilder) reset() {
 }
 
 func (eqb *ExtendedQueryBuilder) encodeExtendedParamValue(m *pgtype.Map, oid uint32, formatCode int16, arg any) ([]byte, error) {
-	if anynil.Is(arg) {
-		return nil, nil
-	}
-
 	if eqb.paramValueBytes == nil {
 		eqb.paramValueBytes = make([]byte, 0, 128)
 	}
diff --git a/pgtype/pgtype.go b/pgtype/pgtype.go
index 2be11e820..810eb5771 100644
--- a/pgtype/pgtype.go
+++ b/pgtype/pgtype.go
@@ -9,6 +9,8 @@ import (
 	"net/netip"
 	"reflect"
 	"time"
+
+	"github.com/jackc/pgx/v5/internal/anynil"
 )
 
 // PostgreSQL oids for common types
@@ -1912,7 +1914,7 @@ func newEncodeError(value any, m *Map, oid uint32, formatCode int16, err error)
 // (nil, nil). The caller of Encode is responsible for writing the correct NULL value or the length of the data
 // written.
 func (m *Map) Encode(oid uint32, formatCode int16, value any, buf []byte) (newBuf []byte, err error) {
-	if value == nil {
+	if anynil.Is(value) {
 		return nil, nil
 	}
 
diff --git a/values.go b/values.go
index cab717d0a..6e2ff3003 100644
--- a/values.go
+++ b/values.go
@@ -3,7 +3,6 @@ package pgx
 import (
 	"errors"
 
-	"github.com/jackc/pgx/v5/internal/anynil"
 	"github.com/jackc/pgx/v5/internal/pgio"
 	"github.com/jackc/pgx/v5/pgtype"
 )
@@ -15,10 +14,6 @@ const (
 )
 
 func convertSimpleArgument(m *pgtype.Map, arg any) (any, error) {
-	if anynil.Is(arg) {
-		return nil, nil
-	}
-
 	buf, err := m.Encode(0, TextFormatCode, arg, []byte{})
 	if err != nil {
 		return nil, err
@@ -30,10 +25,6 @@ func convertSimpleArgument(m *pgtype.Map, arg any) (any, error) {
 }
 
 func encodeCopyValue(m *pgtype.Map, buf []byte, oid uint32, arg any) ([]byte, error) {
-	if anynil.Is(arg) {
-		return pgio.AppendInt32(buf, -1), nil
-	}
-
 	sp := len(buf)
 	buf = pgio.AppendInt32(buf, -1)
 	argBuf, err := m.Encode(oid, BinaryFormatCode, arg, buf)