diff --git a/client/client.go b/client/client.go
index 7531054d..dae930e1 100644
--- a/client/client.go
+++ b/client/client.go
@@ -3,6 +3,7 @@ package client
 import (
 	"context"
 	"errors"
+	"regexp"
 
 	"github.com/Azure/azure-sdk-for-go/services/subscription/mgmt/2020-09-01/subscription"
 	// Import all autorest modules
@@ -14,6 +15,10 @@ import (
 	"github.com/hashicorp/go-hclog"
 )
 
+var (
+	SubscriptionIdRegex = regexp.MustCompile(`^[0-9A-Fa-f]{8}-([0-9A-Fa-f]{4}-){3}[0-9A-Fa-f]{12}$`)
+)
+
 type Client struct {
 	subscriptions []string
 	services      map[string]*services.Services
@@ -98,6 +103,14 @@ func Configure(logger hclog.Logger, config interface{}) (schema.ClientMeta, diag
 		logger.Info("No subscriptions specified going to using all available ones", "subscriptions", subscriptions)
 	}
 
+	// validate subscriptions
+	for i, subscriptionId := range client.subscriptions {
+		if !validateSubscriptionId(subscriptionId) {
+			logger.Error("Invalid subscription id", "subscription_id", subscriptionId)
+			client.subscriptions = append(client.subscriptions[:i], client.subscriptions[i+1:]...)
+		}
+	}
+
 	if len(client.subscriptions) == 0 {
 		return nil, diag.FromError(errors.New("could not find any subscription"), diag.USER)
 	}
@@ -113,3 +126,7 @@ func Configure(logger hclog.Logger, config interface{}) (schema.ClientMeta, diag
 	// Return the initialized client and it will be passed to your resources
 	return client, nil
 }
+
+func validateSubscriptionId(subscriptionId string) bool {
+	return SubscriptionIdRegex.MatchString(subscriptionId)
+}