diff --git a/core/auth/auth.go b/core/auth/auth.go
index 98ccaefaa..8eb30d1c3 100644
--- a/core/auth/auth.go
+++ b/core/auth/auth.go
@@ -14,7 +14,7 @@ import (
 type credentialType string
 
 type Credentials struct {
-	STACKIT_SERVICE_ACCOUNT_EMAIL    string
+	STACKIT_SERVICE_ACCOUNT_EMAIL    string // Deprecated: ServiceAccountEmail is not required and will be removed after 12th June 2025.
 	STACKIT_SERVICE_ACCOUNT_TOKEN    string
 	STACKIT_SERVICE_ACCOUNT_KEY_PATH string
 	STACKIT_PRIVATE_KEY_PATH         string
@@ -246,6 +246,8 @@ func readCredential(cred credentialType, credentials *Credentials) (string, erro
 
 // getServiceAccountEmail searches for an email in the following order: client configuration, environment variable, credentials file.
 // is not required for authentication, so it can be empty.
+//
+// Deprecated: ServiceAccountEmail is not required and will be removed after 12th June 2025.
 func getServiceAccountEmail(cfg *config.Configuration) string {
 	if cfg.ServiceAccountEmail != "" {
 		return cfg.ServiceAccountEmail
diff --git a/core/clients/token_flow.go b/core/clients/token_flow.go
index 5aad94321..3748c4dc8 100644
--- a/core/clients/token_flow.go
+++ b/core/clients/token_flow.go
@@ -19,6 +19,7 @@ type TokenFlow struct {
 
 // TokenFlowConfig is the flow config
 type TokenFlowConfig struct {
+	// Deprecated: ServiceAccountEmail is not required and will be removed after 12th June 2025.
 	ServiceAccountEmail string
 	ServiceAccountToken string
 	// Deprecated: retry options were removed to reduce complexity of the client. If this functionality is needed, you can provide your own custom HTTP client.
diff --git a/core/config/config.go b/core/config/config.go
index 2757d4f66..82a7bac9d 100644
--- a/core/config/config.go
+++ b/core/config/config.go
@@ -81,7 +81,7 @@ type Configuration struct {
 	UserAgent             string            `json:"userAgent,omitempty"`
 	Debug                 bool              `json:"debug,omitempty"`
 	NoAuth                bool              `json:"noAuth,omitempty"`
-	ServiceAccountEmail   string            `json:"serviceAccountEmail,omitempty"`
+	ServiceAccountEmail   string            `json:"serviceAccountEmail,omitempty"` // Deprecated: ServiceAccountEmail is not required and will be removed after 12th June 2025.
 	Token                 string            `json:"token,omitempty"`
 	ServiceAccountKey     string            `json:"serviceAccountKey,omitempty"`
 	PrivateKey            string            `json:"privateKey,omitempty"`
@@ -176,6 +176,8 @@ func WithTokenEndpoint(url string) ConfigurationOption {
 }
 
 // WithServiceAccountEmail returns a ConfigurationOption that sets the service account email
+//
+// Deprecated: WithServiceAccountEmail is not required and will be removed after 12th June 2025.
 func WithServiceAccountEmail(serviceAccountEmail string) ConfigurationOption {
 	return func(config *Configuration) error {
 		config.ServiceAccountEmail = serviceAccountEmail
@@ -319,7 +321,6 @@ func WithCustomConfiguration(cfg *Configuration) ConfigurationOption {
 		config.NoAuth = cfg.NoAuth
 		config.Token = cfg.Token
 		config.ServiceAccountKey = cfg.ServiceAccountKey
-		config.ServiceAccountEmail = cfg.ServiceAccountEmail
 		config.ServiceAccountKeyPath = cfg.ServiceAccountKeyPath
 		config.PrivateKey = cfg.PrivateKey
 		config.PrivateKeyPath = cfg.PrivateKeyPath