diff --git a/README.md b/README.md
index aba5fb99..65de7880 100644
--- a/README.md
+++ b/README.md
@@ -470,20 +470,20 @@ endpoints:
 
 
 #### Configuring Email alerts
-| Parameter                          | Description                                                                                | Default       |
-|:-----------------------------------|:-------------------------------------------------------------------------------------------|:--------------|
-| `alerting.email`                   | Configuration for alerts of type `email`                                                   | `{}`          |
-| `alerting.email.from`              | Email used to send the alert                                                               | Required `""` |
-| `alerting.email.username`          | Username of the SMTP server used to send the alert. If empty, uses `alerting.email.from`.  | `""`          |
-| `alerting.email.password`          | Password of the SMTP server used to send the alert                                         | Required `""` |
-| `alerting.email.host`              | Host of the mail server (e.g. `smtp.gmail.com`)                                            | Required `""` |
-| `alerting.email.port`              | Port the mail server is listening to (e.g. `587`)                                          | Required `0`  |
-| `alerting.email.to`                | Email(s) to send the alerts to                                                             | Required `""` |
-| `alerting.email.default-alert`     | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert) | N/A           |
-| `alerting.email.client.insecure`   | Whether to skip TLS verification                                                           | `false`       |
-| `alerting.email.overrides`         | List of overrides that may be prioritized over the default configuration                   | `[]`          |
-| `alerting.email.overrides[].group` | Endpoint group for which the configuration will be overridden by this configuration        | `""`          |
-| `alerting.email.overrides[].to`    | Email(s) to send the alerts to                                                             | `""`          |
+| Parameter                          | Description                                                                                   | Default       |
+|:-----------------------------------|:----------------------------------------------------------------------------------------------|:--------------|
+| `alerting.email`                   | Configuration for alerts of type `email`                                                      | `{}`          |
+| `alerting.email.from`              | Email used to send the alert                                                                  | Required `""` |
+| `alerting.email.username`          | Username of the SMTP server used to send the alert. If empty, uses `alerting.email.from`.     | `""`          |
+| `alerting.email.password`          | Password of the SMTP server used to send the alert. If empty, no authentication is performed. | `""`          |
+| `alerting.email.host`              | Host of the mail server (e.g. `smtp.gmail.com`)                                               | Required `""` |
+| `alerting.email.port`              | Port the mail server is listening to (e.g. `587`)                                             | Required `0`  |
+| `alerting.email.to`                | Email(s) to send the alerts to                                                                | Required `""` |
+| `alerting.email.default-alert`     | Default alert configuration. <br />See [Setting a default alert](#setting-a-default-alert)    | N/A           |
+| `alerting.email.client.insecure`   | Whether to skip TLS verification                                                              | `false`       |
+| `alerting.email.overrides`         | List of overrides that may be prioritized over the default configuration                      | `[]`          |
+| `alerting.email.overrides[].group` | Endpoint group for which the configuration will be overridden by this configuration           | `""`          |
+| `alerting.email.overrides[].to`    | Email(s) to send the alerts to                                                                | `""`          |
 
 ```yaml
 alerting:
diff --git a/alerting/provider/email/email.go b/alerting/provider/email/email.go
index 2729d38e..47940cae 100644
--- a/alerting/provider/email/email.go
+++ b/alerting/provider/email/email.go
@@ -49,7 +49,7 @@ func (provider *AlertProvider) IsValid() bool {
 		}
 	}
 
-	return len(provider.From) > 0 && len(provider.Password) > 0 && len(provider.Host) > 0 && len(provider.To) > 0 && provider.Port > 0 && provider.Port < math.MaxUint16
+	return len(provider.From) > 0 && len(provider.Host) > 0 && len(provider.To) > 0 && provider.Port > 0 && provider.Port < math.MaxUint16
 }
 
 // Send an alert using the provider
@@ -66,7 +66,20 @@ func (provider *AlertProvider) Send(endpoint *core.Endpoint, alert *alert.Alert,
 	m.SetHeader("To", strings.Split(provider.getToForGroup(endpoint.Group), ",")...)
 	m.SetHeader("Subject", subject)
 	m.SetBody("text/plain", body)
-	d := gomail.NewDialer(provider.Host, provider.Port, username, provider.Password)
+	var d *gomail.Dialer
+	if len(provider.Password) == 0 {
+		// Get the domain in the From address
+		localName := "localhost"
+		fromParts := strings.Split(provider.From, `@`)
+		if len(fromParts) == 2 {
+			localName = fromParts[1]
+		}
+		// Create a dialer with no authentication
+		d = &gomail.Dialer{Host: provider.Host, Port: provider.Port, LocalName: localName}
+	} else {
+		// Create an authenticated dialer
+		d = gomail.NewDialer(provider.Host, provider.Port, username, provider.Password)
+	}
 	if provider.ClientConfig != nil && provider.ClientConfig.Insecure {
 		d.TLSConfig = &tls.Config{InsecureSkipVerify: true}
 	}
diff --git a/alerting/provider/email/email_test.go b/alerting/provider/email/email_test.go
index e409ca05..325432a3 100644
--- a/alerting/provider/email/email_test.go
+++ b/alerting/provider/email/email_test.go
@@ -18,6 +18,13 @@ func TestAlertDefaultProvider_IsValid(t *testing.T) {
 	}
 }
 
+func TestAlertProvider_IsValidWithNoCredentials(t *testing.T) {
+	validProvider := AlertProvider{From: "from@example.com", Host: "smtp-relay.gmail.com", Port: 587, To: "to@example.com"}
+	if !validProvider.IsValid() {
+		t.Error("provider should've been valid")
+	}
+}
+
 func TestAlertProvider_IsValidWithOverride(t *testing.T) {
 	providerWithInvalidOverrideGroup := AlertProvider{
 		Overrides: []Override{