diff --git a/internal/services/users/user_data_source.go b/internal/services/users/user_data_source.go
index 54c9b3b188..3e2ed8840f 100644
--- a/internal/services/users/user_data_source.go
+++ b/internal/services/users/user_data_source.go
@@ -14,6 +14,7 @@ import (
 
 	"github.com/hashicorp/terraform-provider-azuread/internal/clients"
 	"github.com/hashicorp/terraform-provider-azuread/internal/tf"
+	"github.com/hashicorp/terraform-provider-azuread/internal/utils"
 	"github.com/hashicorp/terraform-provider-azuread/internal/validate"
 )
 
@@ -316,7 +317,7 @@ func userDataSourceRead(ctx context.Context, d *schema.ResourceData, meta interf
 
 	if upn, ok := d.Get("user_principal_name").(string); ok && upn != "" {
 		query := odata.Query{
-			Filter: fmt.Sprintf("userPrincipalName eq '%s'", upn),
+			Filter: fmt.Sprintf("userPrincipalName eq '%s'", utils.EscapeSingleQuote(upn)),
 		}
 		users, _, err := client.List(ctx, query)
 		if err != nil {
diff --git a/internal/services/users/users_data_source.go b/internal/services/users/users_data_source.go
index d0a4169880..fee72eff0e 100644
--- a/internal/services/users/users_data_source.go
+++ b/internal/services/users/users_data_source.go
@@ -17,6 +17,7 @@ import (
 
 	"github.com/hashicorp/terraform-provider-azuread/internal/clients"
 	"github.com/hashicorp/terraform-provider-azuread/internal/tf"
+	"github.com/hashicorp/terraform-provider-azuread/internal/utils"
 	"github.com/hashicorp/terraform-provider-azuread/internal/validate"
 )
 
@@ -179,7 +180,7 @@ func usersDataSourceRead(ctx context.Context, d *schema.ResourceData, meta inter
 		expectedCount = len(upns)
 		for _, v := range upns {
 			query := odata.Query{
-				Filter: fmt.Sprintf("userPrincipalName eq '%s'", v),
+				Filter: fmt.Sprintf("userPrincipalName eq '%s'", utils.EscapeSingleQuote(v.(string))),
 			}
 			result, _, err := client.List(ctx, query)
 			if err != nil {