diff --git a/cli/CHANGELOG.md b/cli/CHANGELOG.md
index ea500ae914d3..8d201ca014ab 100644
--- a/cli/CHANGELOG.md
+++ b/cli/CHANGELOG.md
@@ -17,7 +17,7 @@ _Released 10/03/2023 (PENDING)_
 _Released 09/27/2023_
 
 **Features:**
-
+ - Added ability to specify the default running browser in cypress config. Addresses [#6646](https://github.com/cypress-io/cypress/issues/6646).
  - Introduces new layout for Runs page providing additional run information. Addresses [#27203](https://github.com/cypress-io/cypress/issues/27203).
 
 **Bugfixes:**
diff --git a/cli/types/cypress.d.ts b/cli/types/cypress.d.ts
index a40f2fcdf92c..388bed538127 100644
--- a/cli/types/cypress.d.ts
+++ b/cli/types/cypress.d.ts
@@ -3180,6 +3180,11 @@ declare namespace Cypress {
     setupNodeEvents: (on: PluginEvents, config: PluginConfigOptions) => Promise<PluginConfigOptions | void> | PluginConfigOptions | void
 
     indexHtmlFile: string
+
+    /**
+     * Set a default browser other than electron when user doesn't pass in "--browser".
+     */
+    defaultBrowser: string
   }
 
   interface EndToEndConfigOptions extends Omit<CoreConfigOptions, 'indexHtmlFile'> {
@@ -3536,7 +3541,7 @@ declare namespace Cypress {
     hosts?: null | {[key: string]: string}
   }
 
-  interface PluginConfigOptions extends ResolvedConfigOptions, RuntimeConfigOptions {
+  interface PluginConfigOptions extends ResolvedConfigOptions, Omit<RuntimeConfigOptions, 'browser'> {
     /**
     * Absolute path to the root of the project
     */
diff --git a/packages/data-context/src/DataContext.ts b/packages/data-context/src/DataContext.ts
index e59f89233088..ae47e67605af 100644
--- a/packages/data-context/src/DataContext.ts
+++ b/packages/data-context/src/DataContext.ts
@@ -83,7 +83,7 @@ export interface GraphQLRequestInfo {
 export class DataContext {
   readonly graphqlRequestInfo?: GraphQLRequestInfo
   private _config: Omit<DataContextConfig, 'modeOptions'>
-  private _modeOptions: Readonly<Partial<AllModeOptions>>
+  private _modeOptions: Partial<AllModeOptions>
   private _coreData: CoreDataShape
   readonly lifecycleManager: ProjectLifecycleManager
 
@@ -423,4 +423,8 @@ export class DataContext {
       this.#awaitingEmptyRequestCount.push(resolve)
     })
   }
+
+  setModeOptionsBrowser (browser: string) {
+    this._modeOptions.browser = browser
+  }
 }
diff --git a/packages/data-context/src/data/ProjectLifecycleManager.ts b/packages/data-context/src/data/ProjectLifecycleManager.ts
index b41a505d892d..2f5f67a96cfc 100644
--- a/packages/data-context/src/data/ProjectLifecycleManager.ts
+++ b/packages/data-context/src/data/ProjectLifecycleManager.ts
@@ -299,10 +299,29 @@ export class ProjectLifecycleManager {
   /**
    * Sets the initial `activeBrowser` depending on these criteria, in order of preference:
    *  1. The value of `--browser` passed via CLI.
-   *  2. The last browser selected in `open` mode (by name and channel) for this project.
-   *  3. The first browser found.
+   *  2. The value of `defaultBrowser` in `cypress.config`
+   *  3. The last browser selected in `open` mode (by name and channel) for this project.
+   *  4. The first browser found.
    */
   async setInitialActiveBrowser () {
+    const configBrowser = this.loadedFullConfig?.defaultBrowser
+
+    if (configBrowser && !this.ctx.coreData.isBrowserGivenByCli) {
+      await this.setActiveBrowserByNameOrPath(configBrowser)
+
+      if (this.ctx.isRunMode) {
+        this.ctx.setModeOptionsBrowser(configBrowser)
+
+        return
+      }
+
+      if (this.ctx.coreData.activeBrowser) {
+        await this.ctx.actions.project.launchProject(this.ctx.coreData.currentTestingType)
+      }
+
+      return
+    }
+
     if (this.ctx.coreData.cliBrowser) {
       await this.setActiveBrowserByNameOrPath(this.ctx.coreData.cliBrowser)
 
diff --git a/packages/data-context/src/data/coreDataShape.ts b/packages/data-context/src/data/coreDataShape.ts
index d14d17cfedb6..9069c4c28ac0 100644
--- a/packages/data-context/src/data/coreDataShape.ts
+++ b/packages/data-context/src/data/coreDataShape.ts
@@ -142,6 +142,7 @@ interface CloudDataShape {
 
 export interface CoreDataShape {
   cliBrowser: string | null
+  isBrowserGivenByCli: boolean
   cliTestingType: string | null
   activeBrowser: FoundBrowser | null
   machineId: Promise<string | null>
@@ -180,6 +181,7 @@ export function makeCoreData (modeOptions: Partial<AllModeOptions> = {}): CoreDa
   return {
     servers: {},
     cliBrowser: modeOptions.browser ?? null,
+    isBrowserGivenByCli: modeOptions.isBrowserGivenByCli ?? false,
     cliTestingType: modeOptions.testingType ?? null,
     machineId: machineId(),
     machineBrowsers: null,
diff --git a/packages/server/lib/modes/index.ts b/packages/server/lib/modes/index.ts
index c542b7d807b9..99b7085e8e5f 100644
--- a/packages/server/lib/modes/index.ts
+++ b/packages/server/lib/modes/index.ts
@@ -10,6 +10,8 @@ export = (mode, options) => {
     return require('./smoke_test').run(options)
   }
 
+  options.isBrowserGivenByCli = options.browser !== undefined
+
   if (mode === 'run') {
     _.defaults(options, {
       socketId: random.id(10),
diff --git a/packages/types/src/modeOptions.ts b/packages/types/src/modeOptions.ts
index f8ab17f81ec2..1b8b09e8afea 100644
--- a/packages/types/src/modeOptions.ts
+++ b/packages/types/src/modeOptions.ts
@@ -1,6 +1,7 @@
 export interface CommonModeOptions {
   _?: (string | null)[] | null
   invokedFromCli: boolean
+  isBrowserGivenByCli: boolean
   userNodePath?: string
   userNodeVersion?: string
   configFile?: string | null
diff --git a/system-tests/projects/config-default-browser/cypress.config.js b/system-tests/projects/config-default-browser/cypress.config.js
new file mode 100644
index 000000000000..20d060ec1140
--- /dev/null
+++ b/system-tests/projects/config-default-browser/cypress.config.js
@@ -0,0 +1,8 @@
+const { defineConfig } = require('cypress')
+
+module.exports = defineConfig({
+  e2e: {
+    supportFile: false,
+  },
+  defaultBrowser: 'chrome',
+})
diff --git a/system-tests/projects/config-default-browser/cypress/e2e/spec.cy.js b/system-tests/projects/config-default-browser/cypress/e2e/spec.cy.js
new file mode 100644
index 000000000000..434d054dfaa1
--- /dev/null
+++ b/system-tests/projects/config-default-browser/cypress/e2e/spec.cy.js
@@ -0,0 +1,3 @@
+it('works', () => {
+  expect(1).to.eq(1)
+})
diff --git a/system-tests/test/config_spec.js b/system-tests/test/config_spec.js
index b71c4a206a37..c0ba42a8c0e6 100644
--- a/system-tests/test/config_spec.js
+++ b/system-tests/test/config_spec.js
@@ -243,4 +243,15 @@ describe('e2e config', () => {
       snapshot: true,
     })
   })
+
+  it('launches browser using config.defaultBrowser', async function () {
+    await Fixtures.scaffoldProject('config-default-browser')
+
+    return systemTests.exec(this, {
+      project: 'config-default-browser',
+      onStdout: (stdout) => {
+        expect(stdout).to.include('Browser:    Chrome')
+      },
+    })
+  })
 })