diff --git a/packages/routers/src/StackRouter.tsx b/packages/routers/src/StackRouter.tsx
index 06ff78b6..3ea057c3 100644
--- a/packages/routers/src/StackRouter.tsx
+++ b/packages/routers/src/StackRouter.tsx
@@ -434,13 +434,7 @@ export default function StackRouter(options: StackRouterOptions) {
                     }
                   : route.params;
             } else {
-              params =
-                routeParamList[route.name] !== undefined
-                  ? {
-                      ...routeParamList[route.name],
-                      ...action.payload.params,
-                    }
-                  : action.payload.params;
+              params = action.payload.params;
             }
 
             return {
diff --git a/packages/routers/src/TabRouter.tsx b/packages/routers/src/TabRouter.tsx
index 83d567a2..59586038 100644
--- a/packages/routers/src/TabRouter.tsx
+++ b/packages/routers/src/TabRouter.tsx
@@ -326,13 +326,7 @@ export default function TabRouter({
                         }
                       : route.params;
                 } else {
-                  params =
-                    routeParamList[route.name] !== undefined
-                      ? {
-                          ...routeParamList[route.name],
-                          ...action.payload.params,
-                        }
-                      : action.payload.params;
+                  params = action.payload.params;
                 }
 
                 const path =
diff --git a/packages/routers/src/__tests__/StackRouter.test.tsx b/packages/routers/src/__tests__/StackRouter.test.tsx
index 336dd7e8..12390ab1 100644
--- a/packages/routers/src/__tests__/StackRouter.test.tsx
+++ b/packages/routers/src/__tests__/StackRouter.test.tsx
@@ -1487,7 +1487,7 @@ it("doesn't merge params on navigate to an existing screen", () => {
     routeNames: ['baz', 'bar', 'qux'],
     routes: [
       { key: 'baz', name: 'baz' },
-      { key: 'bar', name: 'bar', params: { color: 'test' } },
+      { key: 'bar', name: 'bar' },
     ],
   });
 
@@ -1515,7 +1515,7 @@ it("doesn't merge params on navigate to an existing screen", () => {
     routeNames: ['baz', 'bar', 'qux'],
     routes: [
       { key: 'baz', name: 'baz' },
-      { key: 'bar', name: 'bar', params: { color: 'test', fruit: 'orange' } },
+      { key: 'bar', name: 'bar', params: { fruit: 'orange' } },
     ],
   });
 });
diff --git a/packages/routers/src/__tests__/TabRouter.test.tsx b/packages/routers/src/__tests__/TabRouter.test.tsx
index 291d6723..008a917b 100644
--- a/packages/routers/src/__tests__/TabRouter.test.tsx
+++ b/packages/routers/src/__tests__/TabRouter.test.tsx
@@ -1510,7 +1510,7 @@ it("doesn't merge params on navigate to an existing screen", () => {
     routes: [
       { key: 'baz', name: 'baz' },
       { key: 'bar', name: 'bar' },
-      { key: 'qux', name: 'qux', params: { color: 'indigo', test: 12 } },
+      { key: 'qux', name: 'qux', params: { test: 12 } },
     ],
     history: [
       { type: 'route', key: 'baz' },