diff --git a/src/api/auth.c b/src/api/auth.c
index e784e5f3..ce28e13f 100644
--- a/src/api/auth.c
+++ b/src/api/auth.c
@@ -57,13 +57,16 @@
 
 static struct {
 	bool used;
-	bool tls;
+	struct {
+		bool login;
+		bool mixed;
+	} tls;
 	time_t login_at;
 	time_t valid_until;
 	char remote_addr[48]; // Large enough for IPv4 and IPv6 addresses, hard-coded in civetweb.h as mg_request_info.remote_addr
 	char user_agent[128];
 	char sid[SID_SIZE];
-} auth_data[API_MAX_CLIENTS] = {{false, false, 0, 0, {0}, {0}, {0}}};
+} auth_data[API_MAX_CLIENTS] = {{false, {false, false}, 0, 0, {0}, {0}, {0}}};
 
 #define CHALLENGE_SIZE (2*SHA256_DIGEST_SIZE)
 static struct {
@@ -194,6 +197,9 @@ int check_client_auth(struct ftl_conn *api)
 		// the validity of their API authentication
 		auth_data[user_id].valid_until = now + config.webserver.sessionTimeout.v.ui;
 
+		// Set strict_tls permanently to false if the client connected via HTTP
+		auth_data[user_id].tls.mixed |= api->request->is_ssl != auth_data[user_id].tls.login;
+
 		// Update user cookie
 		if(snprintf(pi_hole_extra_headers, sizeof(pi_hole_extra_headers),
 		            FTL_SET_COOKIE,
@@ -253,7 +259,10 @@ static int get_all_sessions(struct ftl_conn *api, cJSON *json)
 		JSON_ADD_NUMBER_TO_OBJECT(session, "id", i);
 		JSON_ADD_BOOL_TO_OBJECT(session, "current_session", i == api->user_id);
 		JSON_ADD_BOOL_TO_OBJECT(session, "valid", auth_data[i].valid_until >= now);
-		JSON_ADD_BOOL_TO_OBJECT(session, "tls", auth_data[i].tls);
+		cJSON *tls = JSON_NEW_OBJECT();
+		JSON_ADD_BOOL_TO_OBJECT(tls, "login", auth_data[i].tls.login);
+		JSON_ADD_BOOL_TO_OBJECT(tls, "mixed", auth_data[i].tls.mixed);
+		JSON_ADD_ITEM_TO_OBJECT(session, "tls", tls);
 		JSON_ADD_NUMBER_TO_OBJECT(session, "login_at", auth_data[i].login_at);
 		JSON_ADD_NUMBER_TO_OBJECT(session, "last_active", auth_data[i].valid_until - config.webserver.sessionTimeout.v.ui);
 		JSON_ADD_NUMBER_TO_OBJECT(session, "valid_until", auth_data[i].valid_until);
@@ -584,7 +593,8 @@ int api_auth(struct ftl_conn *api)
 						auth_data[i].user_agent[0] = '\0';
 					}
 
-					auth_data[i].tls = api->request->is_ssl;
+					auth_data[i].tls.login = api->request->is_ssl;
+					auth_data[i].tls.mixed = false;
 
 					// Generate new SID
 					generateSID(auth_data[i].sid);
diff --git a/src/api/docs/content/specs/auth.yaml b/src/api/docs/content/specs/auth.yaml
index 6dc74975..c6540677 100644
--- a/src/api/docs/content/specs/auth.yaml
+++ b/src/api/docs/content/specs/auth.yaml
@@ -265,8 +265,15 @@ components:
                 type: boolean
                 description: Valid session indicator (existing sessions may be invalid due to timeout)
               tls:
-                type: boolean
-                description: Indicator if TLS (end-to-end encryption) is used for this session
+                type: object
+                description: TLS (end-to-end encryption) information
+                properties:
+                  login:
+                    type: boolean
+                    description: Indicator if TLS (end-to-end encryption) has been used during login for this session
+                  mixed:
+                    type: boolean
+                    description: Indicator if TLS (end-to-end encryption) is used only partially for this session
               login_at:
                 type: integer
                 description: Timestamp of login (seconds since epoch)
@@ -284,7 +291,12 @@ components:
                 description: User agent of the client
           example:
             - id: 1
+              current_session: true
               valid: true
+              tls:
+                login: true
+                mixed: false
+              strict_tls: false
               login_at: 1580000000
               last_active: 1580000000
               valid_until: 1580000300