diff --git a/scw/locality.go b/scw/locality.go
index a71ca1f6..1dc7b9e4 100644
--- a/scw/locality.go
+++ b/scw/locality.go
@@ -2,10 +2,18 @@ package scw
 
 import (
 	"encoding/json"
+	"regexp"
+	"strings"
 
+	"github.com/scaleway/scaleway-sdk-go/internal/errors"
 	"github.com/scaleway/scaleway-sdk-go/logger"
 )
 
+var (
+	regionRegex = regexp.MustCompile("^[a-z]{2}-[a-z]{3}$")
+	zoneRegex   = regexp.MustCompile("^[a-z]{2}-[a-z]{3}-[1-9]$")
+)
+
 // Zone is an availability zone
 type Zone string
 
@@ -77,7 +85,7 @@ func (region Region) GetZones() []Zone {
 	}
 }
 
-// ParseZone parse a string value into a Zone object
+// ParseZone parses a string value into a Zone and returns an error if it has a bad format.
 func ParseZone(zone string) (Zone, error) {
 	switch zone {
 	case "par1":
@@ -89,6 +97,14 @@ func ParseZone(zone string) (Zone, error) {
 		// logger.Warningf("ams1 is a deprecated name for zone, use nl-ams-1 instead")
 		return ZoneNlAms1, nil
 	default:
+		if !zoneRegex.Match([]byte(zone)) {
+			zones := []string(nil)
+			for _, z := range AllZones {
+				zones = append(zones, string(z))
+			}
+			return "", errors.New("wrong zone format, available zones are: %s", strings.Join(zones, ", "))
+		}
+
 		newZone := Zone(zone)
 		if !newZone.Exists() {
 			logger.Warningf("%s is an unknown zone", newZone)
@@ -116,7 +132,7 @@ func (zone *Zone) UnmarshalJSON(input []byte) error {
 	return nil
 }
 
-// ParseRegion parse a string value into a Zone object
+// ParseRegion parses a string value into a Region and returns an error if it has a bad format.
 func ParseRegion(region string) (Region, error) {
 	switch region {
 	case "par1":
@@ -128,6 +144,14 @@ func ParseRegion(region string) (Region, error) {
 		// logger.Warningf("ams1 is a deprecated name for region, use nl-ams instead")
 		return RegionNlAms, nil
 	default:
+		if !regionRegex.Match([]byte(region)) {
+			regions := []string(nil)
+			for _, r := range AllRegions {
+				regions = append(regions, string(r))
+			}
+			return "", errors.New("wrong region format, available regions are: %s", strings.Join(regions, ", "))
+		}
+
 		newRegion := Region(region)
 		if !newRegion.Exists() {
 			logger.Warningf("%s is an unknown region", newRegion)
diff --git a/scw/locality_test.go b/scw/locality_test.go
index 2ae5fe48..9784b559 100644
--- a/scw/locality_test.go
+++ b/scw/locality_test.go
@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"testing"
 
+	"github.com/scaleway/scaleway-sdk-go/internal/errors"
 	"github.com/scaleway/scaleway-sdk-go/internal/testhelpers"
 )
 
@@ -11,6 +12,7 @@ func TestParseZone(t *testing.T) {
 
 	tests := []struct {
 		input    string
+		err      error
 		expected Zone
 	}{
 		{
@@ -25,12 +27,33 @@ func TestParseZone(t *testing.T) {
 			input:    "ams1",
 			expected: ZoneNlAms1,
 		},
+		{
+			input:    "xx-xxx-1",
+			expected: "xx-xxx-1",
+		},
+		{
+			input:    "fr-par",
+			expected: "",
+			err:      errors.New("wrong zone format, available zones are: fr-par-1, fr-par-2, nl-ams-1"),
+		},
+		{
+			input:    "fr-par-n",
+			expected: "",
+			err:      errors.New("wrong zone format, available zones are: fr-par-1, fr-par-2, nl-ams-1"),
+		},
+		{
+			input:    "fr-par-0",
+			expected: "",
+			err:      errors.New("wrong zone format, available zones are: fr-par-1, fr-par-2, nl-ams-1"),
+		},
 	}
 
 	for _, test := range tests {
-		z, err := ParseZone(test.input)
-		testhelpers.AssertNoError(t, err)
-		testhelpers.Equals(t, test.expected, z)
+		t.Run(test.input, func(t *testing.T) {
+			z, err := ParseZone(test.input)
+			testhelpers.Equals(t, test.err, err)
+			testhelpers.Equals(t, test.expected, z)
+		})
 	}
 
 }
@@ -67,6 +90,7 @@ func TestParseRegion(t *testing.T) {
 
 	tests := []struct {
 		input    string
+		err      error
 		expected Region
 	}{
 		{
@@ -81,12 +105,28 @@ func TestParseRegion(t *testing.T) {
 			input:    "ams1",
 			expected: RegionNlAms,
 		},
+		{
+			input:    "xx-xxx",
+			expected: "xx-xxx",
+		},
+		{
+			input:    "fr-par-1",
+			expected: "",
+			err:      errors.New("wrong region format, available regions are: fr-par, nl-ams"),
+		},
+		{
+			input:    "fr-pa1",
+			expected: "",
+			err:      errors.New("wrong region format, available regions are: fr-par, nl-ams"),
+		},
 	}
 
 	for _, test := range tests {
-		r, err := ParseRegion(test.input)
-		testhelpers.AssertNoError(t, err)
-		testhelpers.Equals(t, test.expected, r)
+		t.Run(test.input, func(t *testing.T) {
+			r, err := ParseRegion(test.input)
+			testhelpers.Equals(t, test.err, err)
+			testhelpers.Equals(t, test.expected, r)
+		})
 	}
 
 }