diff --git a/plugin/auth/viessmann.go b/plugin/auth/viessmann.go
index 5de4143df..89caad8b7 100644
--- a/plugin/auth/viessmann.go
+++ b/plugin/auth/viessmann.go
@@ -3,28 +3,21 @@ package auth
 import (
 	"context"
 
+	"dario.cat/mergo"
 	"github.com/evcc-io/evcc/util"
 	"github.com/evcc-io/evcc/util/request"
 	"golang.org/x/oauth2"
 )
 
-const (
-	OAuthURI    = "https://iam.viessmann-climatesolutions.com/idp/v3"
-	RedirectURI = "http://localhost:4200/"
-	// ^ the value of RedirectURI doesn't matter, but it must be the same between requests
-)
+const OAuthURI = "https://iam.viessmann-climatesolutions.com/idp/v3"
 
-func oauth2Config(clientID string) *oauth2.Config {
-	return &oauth2.Config{
-		ClientID: clientID,
-		Endpoint: oauth2.Endpoint{
-			AuthURL:   OAuthURI + "/authorize",
-			TokenURL:  OAuthURI + "/token",
-			AuthStyle: oauth2.AuthStyleInHeader,
-		},
-		RedirectURL: RedirectURI,
-		Scopes:      []string{"IoT User", "offline_access"},
-	}
+var oauthConfig = oauth2.Config{
+	Endpoint: oauth2.Endpoint{
+		AuthURL:   OAuthURI + "/authorize",
+		TokenURL:  OAuthURI + "/token",
+		AuthStyle: oauth2.AuthStyleInHeader,
+	},
+	Scopes: []string{"IoT User", "offline_access"},
 }
 
 func init() {
@@ -33,8 +26,9 @@ func init() {
 
 func NewViessmannFromConfig(ctx context.Context, other map[string]any) (oauth2.TokenSource, error) {
 	var cc struct {
-		ClientID string
-		Gateway  string
+		ClientID    string
+		RedirectURI string
+		Gateway     string
 	}
 
 	if err := util.DecodeOther(other, &cc); err != nil {
@@ -44,5 +38,13 @@ func NewViessmannFromConfig(ctx context.Context, other map[string]any) (oauth2.T
 	log := util.NewLogger("viessmann").Redact(cc.ClientID)
 	ctx = context.WithValue(ctx, oauth2.HTTPClient, request.NewClient(log))
 
-	return NewOauth(ctx, "Viessmann", cc.Gateway, oauth2Config(cc.ClientID))
+	oc := oauth2.Config{
+		ClientID:    cc.ClientID,
+		RedirectURL: cc.RedirectURI,
+	}
+	if err := mergo.Merge(&oc, oauthConfig); err != nil {
+		return nil, err
+	}
+
+	return NewOauth(ctx, "Viessmann", cc.Gateway, &oc)
 }
diff --git a/templates/definition/charger/viessmann.yaml b/templates/definition/charger/viessmann.yaml
index 74aa960cd..21eb16fb2 100644
--- a/templates/definition/charger/viessmann.yaml
+++ b/templates/definition/charger/viessmann.yaml
@@ -22,6 +22,14 @@ params:
     help:
       de: Konfigurieren in [app.developer.viessmann-climatesolutions.com](https://app.developer.viessmann-climatesolutions.com)
       en: Configure at [app.developer.viessmann-climatesolutions.com](https://app.developer.viessmann-climatesolutions.com)
+  - name: redirecturi
+    required: true
+    description:
+      generic: Redirect URI
+    help:
+      en: "Redirect URI of the evcc instance. Must match the redirect URI set in the Viessmann developer portal."
+      de: "Redirect-URI der evcc-Instanz. Muss mit der Redirect URI übereinstimmen, die Viessmann Developer Portal konfiguriert ist."
+    example: "https://evcc.example.org/providerauth/callback"
   - name: gateway_serial
     required: true
     description:
@@ -50,7 +58,7 @@ params:
         Dann holen wir uns einen oauth token (n.b. am besten den gesamten Block in das Terminal kopieren, da die Zwischenvariable 'CODE' nur 20 Sekunden gültig ist):
 
         ```
-        VIESSMANN_REDIRECT_URI="http://localhost:4200/"
+        VIESSMANN_REDIRECT_URI=<your-redirect-uri>
         VIESSMANN_CODE_CHALLENGE="5M5nhkBfkWZCGfLZYcTL-l7esjPUN7PpZ4rq8k4cmys"
         VIESSMANN_CODE_VERIFIER="6PygdmeK8JKPuuftlkc6q4ceyvjhMM_a_cJrPbcmcLc-SPjx2ZXTYr-SOofPUBydQ3McNYRy7Hibc2L2WtVLJFpOQ~Qbgic455ArKjUz9_UiTLnO6q8A3e.I_fIF8hAo"
 
@@ -92,7 +100,7 @@ params:
         Then execute the following to get an oauth token (n.b. it's best to paste the entire block as-is, since the intermediate 'CODE' is only valid for 20 seconds):
 
         ```
-        VIESSMANN_REDIRECT_URI="http://localhost:4200/"
+        VIESSMANN_REDIRECT_URI=<your-redirect-uri>
         VIESSMANN_CODE_CHALLENGE="5M5nhkBfkWZCGfLZYcTL-l7esjPUN7PpZ4rq8k4cmys"
         VIESSMANN_CODE_VERIFIER="6PygdmeK8JKPuuftlkc6q4ceyvjhMM_a_cJrPbcmcLc-SPjx2ZXTYr-SOofPUBydQ3McNYRy7Hibc2L2WtVLJFpOQ~Qbgic455ArKjUz9_UiTLnO6q8A3e.I_fIF8hAo"
 
@@ -149,6 +157,7 @@ render: |
     auth:
       source: viessmann
       clientid: {{ .clientid }}
+      redirecturi: {{ .redirecturi }}
       gateway: {{ .gateway_serial }}
     jq: '.data.properties.active.value | if . == false then 2 elif . == true then 3 else . end'
     # false -> oneTimeCharge is disabled -> normal mode -> 2
@@ -170,6 +179,7 @@ render: |
           auth:
             source: viessmann
             clientid: {{ .clientid }}
+            redirecturi: {{ .redirecturi }}
             gateway: {{ .gateway_serial }}
           body: >
             { }
@@ -183,6 +193,7 @@ render: |
           auth:
             source: viessmann
             clientid: {{ .clientid }}
+            redirecturi: {{ .redirecturi }}
             gateway: {{ .gateway_serial }}
           body: >
             { }