diff --git a/CHANGELOG-3.11.md b/CHANGELOG-3.11.md
index 1afcd717a8..13762005cc 100644
--- a/CHANGELOG-3.11.md
+++ b/CHANGELOG-3.11.md
@@ -15,6 +15,7 @@ with some extra keywords: backend, tests, test, translation, funders, important
 ### Added
 
 * Edition - Support QGIS dynamic default-value expressions in edit forms, including geometry-based (`$x`, `$y`, `$area`, `$length`, `$geometry`) and field-referencing expressions (e.g. `"firstname" || ' ' || "lastname"`). Defaults are re-evaluated when the geometry is drawn/edited and when a referenced field changes, honoring QGIS's `applyOnUpdate` flag.
+* New per-layer option `excludeFromSingleWMS` to exclude a layer from the bundled "Load layers as a single WMS layer" request. The excluded layer is fetched individually (directly from its WMS server if `externalWmsToggle` is set, otherwise via QGIS Server). Useful for keeping slow third-party WMS layers out of the bundle. Requires the Lizmap plugin ≥ 5.x to expose the toggle in the UI. ([#6631](https://github.com/3liz/lizmap-web-client/issues/6631))
 
 ### Changed
 
diff --git a/assets/src/modules/config/Layer.js b/assets/src/modules/config/Layer.js
index 583a3434a2..8a934dacac 100644
--- a/assets/src/modules/config/Layer.js
+++ b/assets/src/modules/config/Layer.js
@@ -47,6 +47,7 @@ const optionalProperties = {
     'mutuallyExclusive': {type: 'boolean', default: false},
     'externalWmsToggle': {type: 'boolean', default: false},
     'externalAccess': {type: 'object'},
+    'excludeFromSingleWMS': {type: 'boolean', default: false},
 };
 
 /**
@@ -91,6 +92,7 @@ export class LayerConfig extends BaseObjectConfig {
      * @param {boolean}  [cfg.mutuallyExclusive]   - the layer mutuallyExclusive (only group type)
      * @param {boolean}  [cfg.externalWmsToggle]   - the layer provides parameters for external access
      * @param {object}   [cfg.externalAccess]      - the layer external access
+     * @param {boolean}  [cfg.excludeFromSingleWMS] - exclude this layer from the project-level single WMS request bundle (no effect when single WMS is not enabled at project level)
      */
     constructor(cfg) {
         super(cfg, requiredProperties, optionalProperties)
@@ -361,6 +363,15 @@ export class LayerConfig extends BaseObjectConfig {
     get externalAccess() {
         return this._externalAccess;
     }
+
+    /**
+     * Exclude the layer from the project-level single WMS request bundle.
+     * No effect when the project-level "single WMS layer" option is disabled.
+     * @type {boolean}
+     */
+    get excludeFromSingleWMS() {
+        return this._excludeFromSingleWMS;
+    }
 }
 
 /**
diff --git a/assets/src/modules/map.js b/assets/src/modules/map.js
index 9040a1af86..379f0d07d4 100644
--- a/assets/src/modules/map.js
+++ b/assets/src/modules/map.js
@@ -239,7 +239,7 @@ export default class map extends olMap {
                         });
                     }
                 } else {
-                    if(mapState.singleWMSLayer){
+                    if(mapState.singleWMSLayer && !node.layerConfig.excludeFromSingleWMS){
                         this._statesSingleWMSLayers.set(node.name,node);
                         node.singleWMSLayer = true;
                         return
diff --git a/tests/end2end/playwright/singleWMS.spec.js b/tests/end2end/playwright/singleWMS.spec.js
index e1684c2523..ec5f8ba938 100644
--- a/tests/end2end/playwright/singleWMS.spec.js
+++ b/tests/end2end/playwright/singleWMS.spec.js
@@ -463,6 +463,53 @@ test.describe('Single WMS layer', () => {
             await requestSecondBaseLayer.response();
         });
 
+    test('Layer with excludeFromSingleWMS is removed from the bundle and requested individually',
+        {
+            tag:['@readonly']
+        }, async ({ page }) => {
+            // Mark single_wms_lines as excluded from the single WMS request stack.
+            // It should then be requested as its own GetMap (still via QGIS Server,
+            // since no externalAccess is configured on it).
+            await page.route('**/service/getProjectConfig*', async route => {
+                const response = await route.fetch();
+                const json = await response.json();
+                json.layers['single_wms_lines']['excludeFromSingleWMS'] = true;
+                await route.fulfill({ response, json });
+            });
+
+            const project = new ProjectPage(page, 'single_wms_image');
+            const requestBundlePromise = project.waitForSingleWMSGetMapRequest();
+            const requestExcludedPromise = project.waitForGetMapRequest('single_wms_lines');
+            await project.open();
+
+            // Stop intercepting once the project is loaded.
+            await page.unroute('**/service/getProjectConfig*');
+
+            const requestBundle = await requestBundlePromise;
+            const expectedBundleParameters = {
+                'SERVICE': 'WMS',
+                'VERSION': '1.3.0',
+                'REQUEST': 'GetMap',
+                'FORMAT': 'image/png',
+                // single_wms_lines is dropped from the bundle, others kept in order
+                'STYLES':'default,default,default,',
+                'LAYERS':'single_wms_points,single_wms_points_group,single_wms_lines_group,GroupAsLayer',
+            }
+            requestExpect(requestBundle).toContainParametersInUrl(expectedBundleParameters);
+            await requestBundle.response();
+
+            const requestExcluded = await requestExcludedPromise;
+            const expectedExcludedParameters = {
+                'SERVICE': 'WMS',
+                'VERSION': '1.3.0',
+                'REQUEST': 'GetMap',
+                'FORMAT': 'image/png',
+                'LAYERS': 'single_wms_lines',
+            }
+            requestExpect(requestExcluded).toContainParametersInUrl(expectedExcludedParameters);
+            await requestExcluded.response();
+        });
+
     test('Edit a layer',
         {
             tag:['@write']
diff --git a/tests/js-units/node/config/layer.test.js b/tests/js-units/node/config/layer.test.js
index 6b75529a3f..e76ac063c6 100644
--- a/tests/js-units/node/config/layer.test.js
+++ b/tests/js-units/node/config/layer.test.js
@@ -59,6 +59,7 @@ describe('LayerConfig', function () {
         expect(group.cached).to.be.false
         expect(group.clientCacheExpiration).to.be.eq(300)
         expect(group.mutuallyExclusive).to.be.true
+        expect(group.excludeFromSingleWMS).to.be.false
 
         const layer1 = new LayerConfig({
             "id": "null_island20200414115730489",
@@ -128,6 +129,7 @@ describe('LayerConfig', function () {
         expect(layer1.cached).to.be.false
         expect(layer1.clientCacheExpiration).to.be.eq(300)
         expect(layer1.mutuallyExclusive).to.be.false
+        expect(layer1.excludeFromSingleWMS).to.be.false
 
         const layer2 = new LayerConfig({
             "abstract": "",
@@ -196,6 +198,33 @@ describe('LayerConfig', function () {
         expect(layer2.cached).to.be.false
         expect(layer2.clientCacheExpiration).to.be.eq(300)
         expect(layer2.mutuallyExclusive).to.be.false
+        expect(layer2.excludeFromSingleWMS).to.be.false
+
+        const excludedLayer = new LayerConfig({
+            "id": "excluded_wms_layer",
+            "name": "excluded_wms_layer",
+            "type": "layer",
+            "title": "Excluded layer",
+            "abstract": "",
+            "link": "",
+            "minScale": 1,
+            "maxScale": 1000000000000,
+            "toggled": "True",
+            "popup": "False",
+            "popupSource": "auto",
+            "popupTemplate": "",
+            "popupMaxFeatures": 10,
+            "popupDisplayChildren": "False",
+            "groupAsLayer": "False",
+            "baseLayer": "False",
+            "displayInLegend": "True",
+            "singleTile": "True",
+            "imageFormat": "image/png",
+            "cached": "False",
+            "clientCacheExpiration": 300,
+            "excludeFromSingleWMS": true,
+        });
+        expect(excludedLayer.excludeFromSingleWMS).to.be.true
     })
 
     it('ValidationError', function () {