diff --git a/pgtype/circle.go b/pgtype/circle.go
index 7524d7b9..ec136438 100644
--- a/pgtype/circle.go
+++ b/pgtype/circle.go
@@ -11,33 +11,184 @@ import (
 	"github.com/jackc/pgio"
 )
 
+type CircleScanner interface {
+	ScanCircle(v Circle) error
+}
+
+type CircleValuer interface {
+	CircleValue() (Circle, error)
+}
+
 type Circle struct {
 	P     Vec2
 	R     float64
 	Valid bool
 }
 
-func (dst *Circle) Set(src interface{}) error {
-	return fmt.Errorf("cannot convert %v to Circle", src)
+func (c *Circle) ScanCircle(v Circle) error {
+	*c = v
+	return nil
 }
 
-func (dst Circle) Get() interface{} {
-	if !dst.Valid {
-		return nil
-	}
-	return dst
+func (c Circle) CircleValue() (Circle, error) {
+	return c, nil
 }
 
-func (src *Circle) AssignTo(dst interface{}) error {
-	return fmt.Errorf("cannot assign %v to %T", src, dst)
-}
-
-func (dst *Circle) DecodeText(ci *ConnInfo, src []byte) error {
+// Scan implements the database/sql Scanner interface.
+func (dst *Circle) Scan(src interface{}) error {
 	if src == nil {
 		*dst = Circle{}
 		return nil
 	}
 
+	switch src := src.(type) {
+	case string:
+		return scanPlanTextAnyToCircleScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), dst)
+	}
+
+	return fmt.Errorf("cannot scan %T", src)
+}
+
+// Value implements the database/sql/driver Valuer interface.
+func (src Circle) Value() (driver.Value, error) {
+	buf, err := CircleCodec{}.Encode(nil, 0, TextFormatCode, src, nil)
+	if err != nil {
+		return nil, err
+	}
+	return string(buf), err
+}
+
+type CircleCodec struct{}
+
+func (CircleCodec) FormatSupported(format int16) bool {
+	return format == TextFormatCode || format == BinaryFormatCode
+}
+
+func (CircleCodec) PreferredFormat() int16 {
+	return BinaryFormatCode
+}
+
+func (CircleCodec) Encode(ci *ConnInfo, oid uint32, format int16, value interface{}, buf []byte) (newBuf []byte, err error) {
+	if value == nil {
+		return nil, nil
+	}
+
+	var circle Circle
+	if v, ok := value.(CircleValuer); ok {
+		c, err := v.CircleValue()
+		if err != nil {
+			return nil, err
+		}
+		circle = c
+	} else {
+		return nil, fmt.Errorf("cannot convert %v to circle: %v", value, err)
+	}
+
+	if !circle.Valid {
+		return nil, nil
+	}
+
+	switch format {
+	case BinaryFormatCode:
+		buf = pgio.AppendUint64(buf, math.Float64bits(circle.P.X))
+		buf = pgio.AppendUint64(buf, math.Float64bits(circle.P.Y))
+		buf = pgio.AppendUint64(buf, math.Float64bits(circle.R))
+		return buf, nil
+	case TextFormatCode:
+		buf = append(buf, fmt.Sprintf(`<(%s,%s),%s>`,
+			strconv.FormatFloat(circle.P.X, 'f', -1, 64),
+			strconv.FormatFloat(circle.P.Y, 'f', -1, 64),
+			strconv.FormatFloat(circle.R, 'f', -1, 64),
+		)...)
+		return buf, nil
+	default:
+		return nil, fmt.Errorf("unknown format code: %v", format)
+	}
+}
+
+func (CircleCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target interface{}, actualTarget bool) ScanPlan {
+	switch format {
+	case BinaryFormatCode:
+		switch target.(type) {
+		case CircleScanner:
+			return scanPlanBinaryCircleToCircleScanner{}
+		}
+	case TextFormatCode:
+		switch target.(type) {
+		case CircleScanner:
+			return scanPlanTextAnyToCircleScanner{}
+		}
+	}
+
+	return nil
+}
+
+func (c CircleCodec) DecodeDatabaseSQLValue(ci *ConnInfo, oid uint32, format int16, src []byte) (driver.Value, error) {
+	if format == TextFormatCode {
+		return string(src), nil
+	} else {
+		circle, err := c.DecodeValue(ci, oid, format, src)
+		if err != nil {
+			return nil, err
+		}
+		buf, err := c.Encode(ci, oid, TextFormatCode, circle, nil)
+		if err != nil {
+			return nil, err
+		}
+		return string(buf), nil
+	}
+}
+
+func (c CircleCodec) DecodeValue(ci *ConnInfo, oid uint32, format int16, src []byte) (interface{}, error) {
+	if src == nil {
+		return nil, nil
+	}
+
+	var circle Circle
+	scanPlan := c.PlanScan(ci, oid, format, &circle, true)
+	if scanPlan == nil {
+		return nil, fmt.Errorf("PlanScan did not find a plan")
+	}
+	err := scanPlan.Scan(ci, oid, format, src, &circle)
+	if err != nil {
+		return nil, err
+	}
+	return circle, nil
+}
+
+type scanPlanBinaryCircleToCircleScanner struct{}
+
+func (scanPlanBinaryCircleToCircleScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	scanner := (dst).(CircleScanner)
+
+	if src == nil {
+		return scanner.ScanCircle(Circle{})
+	}
+
+	if len(src) != 24 {
+		return fmt.Errorf("invalid length for Circle: %v", len(src))
+	}
+
+	x := binary.BigEndian.Uint64(src)
+	y := binary.BigEndian.Uint64(src[8:])
+	r := binary.BigEndian.Uint64(src[16:])
+
+	return scanner.ScanCircle(Circle{
+		P:     Vec2{math.Float64frombits(x), math.Float64frombits(y)},
+		R:     math.Float64frombits(r),
+		Valid: true,
+	})
+}
+
+type scanPlanTextAnyToCircleScanner struct{}
+
+func (scanPlanTextAnyToCircleScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	scanner := (dst).(CircleScanner)
+
+	if src == nil {
+		return scanner.ScanCircle(Circle{})
+	}
+
 	if len(src) < 9 {
 		return fmt.Errorf("invalid length for Circle: %v", len(src))
 	}
@@ -64,77 +215,5 @@ func (dst *Circle) DecodeText(ci *ConnInfo, src []byte) error {
 		return err
 	}
 
-	*dst = Circle{P: Vec2{x, y}, R: r, Valid: true}
-	return nil
-}
-
-func (dst *Circle) DecodeBinary(ci *ConnInfo, src []byte) error {
-	if src == nil {
-		*dst = Circle{}
-		return nil
-	}
-
-	if len(src) != 24 {
-		return fmt.Errorf("invalid length for Circle: %v", len(src))
-	}
-
-	x := binary.BigEndian.Uint64(src)
-	y := binary.BigEndian.Uint64(src[8:])
-	r := binary.BigEndian.Uint64(src[16:])
-
-	*dst = Circle{
-		P:     Vec2{math.Float64frombits(x), math.Float64frombits(y)},
-		R:     math.Float64frombits(r),
-		Valid: true,
-	}
-	return nil
-}
-
-func (src Circle) EncodeText(ci *ConnInfo, buf []byte) ([]byte, error) {
-	if !src.Valid {
-		return nil, nil
-	}
-
-	buf = append(buf, fmt.Sprintf(`<(%s,%s),%s>`,
-		strconv.FormatFloat(src.P.X, 'f', -1, 64),
-		strconv.FormatFloat(src.P.Y, 'f', -1, 64),
-		strconv.FormatFloat(src.R, 'f', -1, 64),
-	)...)
-
-	return buf, nil
-}
-
-func (src Circle) EncodeBinary(ci *ConnInfo, buf []byte) ([]byte, error) {
-	if !src.Valid {
-		return nil, nil
-	}
-
-	buf = pgio.AppendUint64(buf, math.Float64bits(src.P.X))
-	buf = pgio.AppendUint64(buf, math.Float64bits(src.P.Y))
-	buf = pgio.AppendUint64(buf, math.Float64bits(src.R))
-	return buf, nil
-}
-
-// Scan implements the database/sql Scanner interface.
-func (dst *Circle) Scan(src interface{}) error {
-	if src == nil {
-		*dst = Circle{}
-		return nil
-	}
-
-	switch src := src.(type) {
-	case string:
-		return dst.DecodeText(nil, []byte(src))
-	case []byte:
-		srcCopy := make([]byte, len(src))
-		copy(srcCopy, src)
-		return dst.DecodeText(nil, srcCopy)
-	}
-
-	return fmt.Errorf("cannot scan %T", src)
-}
-
-// Value implements the database/sql/driver Valuer interface.
-func (src Circle) Value() (driver.Value, error) {
-	return EncodeValueText(src)
+	return scanner.ScanCircle(Circle{P: Vec2{x, y}, R: r, Valid: true})
 }
diff --git a/pgtype/circle_test.go b/pgtype/circle_test.go
index 8f39644b..742ac688 100644
--- a/pgtype/circle_test.go
+++ b/pgtype/circle_test.go
@@ -4,13 +4,20 @@ import (
 	"testing"
 
 	"github.com/jackc/pgx/v5/pgtype"
-	"github.com/jackc/pgx/v5/pgtype/testutil"
 )
 
 func TestCircleTranscode(t *testing.T) {
-	testutil.TestSuccessfulTranscode(t, "circle", []interface{}{
-		&pgtype.Circle{P: pgtype.Vec2{1.234, 5.67890123}, R: 3.5, Valid: true},
-		&pgtype.Circle{P: pgtype.Vec2{-1.234, -5.6789}, R: 12.9, Valid: true},
-		&pgtype.Circle{},
+	testPgxCodec(t, "circle", []PgxTranscodeTestCase{
+		{
+			pgtype.Circle{P: pgtype.Vec2{1.234, 5.67890123}, R: 3.5, Valid: true},
+			new(pgtype.Circle),
+			isExpectedEq(pgtype.Circle{P: pgtype.Vec2{1.234, 5.67890123}, R: 3.5, Valid: true}),
+		},
+		{
+			pgtype.Circle{P: pgtype.Vec2{1.234, 5.67890123}, R: 3.5, Valid: true},
+			new(pgtype.Circle),
+			isExpectedEq(pgtype.Circle{P: pgtype.Vec2{1.234, 5.67890123}, R: 3.5, Valid: true}),
+		},
+		{nil, new(pgtype.Circle), isExpectedEq(pgtype.Circle{})},
 	})
 }
diff --git a/pgtype/pgtype.go b/pgtype/pgtype.go
index aedc6dd5..11f7ce0b 100644
--- a/pgtype/pgtype.go
+++ b/pgtype/pgtype.go
@@ -320,7 +320,7 @@ func NewConnInfo() *ConnInfo {
 	ci.RegisterDataType(DataType{Value: &QChar{}, Name: "char", OID: QCharOID})
 	ci.RegisterDataType(DataType{Value: &CID{}, Name: "cid", OID: CIDOID})
 	ci.RegisterDataType(DataType{Value: &CIDR{}, Name: "cidr", OID: CIDROID})
-	ci.RegisterDataType(DataType{Value: &Circle{}, Name: "circle", OID: CircleOID})
+	ci.RegisterDataType(DataType{Name: "circle", OID: CircleOID, Codec: CircleCodec{}})
 	ci.RegisterDataType(DataType{Value: &Date{}, Name: "date", OID: DateOID})
 	// ci.RegisterDataType(DataType{Value: &Daterange{}, Name: "daterange", OID: DaterangeOID})
 	ci.RegisterDataType(DataType{Value: &Float4{}, Name: "float4", OID: Float4OID})
diff --git a/pgtype/zzz.circle.go b/pgtype/zzz.circle.go
deleted file mode 100644
index b111c06d..00000000
--- a/pgtype/zzz.circle.go
+++ /dev/null
@@ -1,35 +0,0 @@
-package pgtype
-
-import "fmt"
-
-func (Circle) BinaryFormatSupported() bool {
-	return true
-}
-
-func (Circle) TextFormatSupported() bool {
-	return true
-}
-
-func (Circle) PreferredFormat() int16 {
-	return BinaryFormatCode
-}
-
-func (dst *Circle) DecodeResult(ci *ConnInfo, oid uint32, format int16, src []byte) error {
-	switch format {
-	case BinaryFormatCode:
-		return dst.DecodeBinary(ci, src)
-	case TextFormatCode:
-		return dst.DecodeText(ci, src)
-	}
-	return fmt.Errorf("unknown format code %d", format)
-}
-
-func (src Circle) EncodeParam(ci *ConnInfo, oid uint32, format int16, buf []byte) (newBuf []byte, err error) {
-	switch format {
-	case BinaryFormatCode:
-		return src.EncodeBinary(ci, buf)
-	case TextFormatCode:
-		return src.EncodeText(ci, buf)
-	}
-	return nil, fmt.Errorf("unknown format code %d", format)
-}