diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9c3fe01f9f..bbcc4aa69f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@
 
 * Add GA4 tracking to related navigation ([PR #3179](https://github.com/alphagov/govuk_publishing_components/pull/3179))
 * Add Youtube Embed Support to the ImageCard Component ([PR #3156](https://github.com/alphagov/govuk_publishing_components/pull/3156))
+* Remove dependency on .js.erb and puppet for loading our analytics ([PR #3145](https://github.com/alphagov/govuk_publishing_components/pull/3145))
 
 ## 34.3.0
 
diff --git a/app/assets/javascripts/govuk_publishing_components/analytics/linked-domains.js b/app/assets/javascripts/govuk_publishing_components/analytics/linked-domains.js
new file mode 100644
index 0000000000..3467358e09
--- /dev/null
+++ b/app/assets/javascripts/govuk_publishing_components/analytics/linked-domains.js
@@ -0,0 +1,135 @@
+// For Universal Analytics' cross domain tracking.
+window.GOVUK.analytics = window.GOVUK.analytics || {}
+window.GOVUK.analytics.linkedDomains = [
+  'access.service.gov.uk',
+  'access.tax.service.gov.uk',
+  'account.companieshouse.gov.uk',
+  'accounts.manage-apprenticeships.service.gov.uk',
+  'account.publishing.service.gov.uk',
+  'add-driving-licence-check-code.service.gov.uk',
+  'analyse-school-performance.service.gov.uk',
+  'appeal-tax-tribunal.service.gov.uk',
+  'apply-basic-criminal-record-check.service.gov.uk',
+  'apply-blue-badge.service.gov.uk',
+  'apply-company-tachograph-card.service.gov.uk',
+  'apply-for-bankruptcy.service.gov.uk',
+  'apply-for-debt-relief-order.service.gov.uk',
+  'apply-for-environmental-permit.service.gov.uk',
+  'apply-for-eu-settled-status.homeoffice.gov.uk',
+  'apply-for-innovation-funding.service.gov.uk',
+  'apply-for-refugee-integration-loan.service.gov.uk',
+  'apply-licence.ozone-depleting-substances.service.gov.uk',
+  'apply-quota.fluorinated-gas.service.gov.uk',
+  'apply-quota.ozone-depleting-substances.service.gov.uk',
+  'apprenticeships.gov.uk',
+  'beta.companieshouse.gov.uk',
+  'biometric-residence-permit.service.gov.uk',
+  'businessreadinessfund.beis.gov.uk',
+  'catchreturn.service.gov.uk',
+  'checklegalaid.service.gov.uk',
+  'check-mot.service.gov.uk',
+  'check-payment-practices.service.gov.uk',
+  'check-vehicle-recalls.service.gov.uk',
+  'civil-service-careers.gov.uk',
+  'civilservicejobs.service.gov.uk',
+  'claim.redundancy-payments.service.gov.uk',
+  'claim-power-of-attorney-refund.service.gov.uk',
+  'compare-school-performance.service.gov.uk',
+  'complete-deputy-report.service.gov.uk',
+  'contractsfinder.service.gov.uk',
+  'coronavirus.data.gov.uk',
+  'coronavirus-business-volunteers.service.gov.uk',
+  'coronavirus-shielding-support.service.gov.uk',
+  'coronavirus-vulnerable-people.service.gov.uk',
+  'courttribunalfinder.service.gov.uk',
+  'create-energy-label.service.gov.uk',
+  'create-qr-code-poster.service.gov.uk',
+  'cymraeg.registertovote.service.gov.uk',
+  'dartford-crossing-charge.service.gov.uk',
+  'design-system.service.gov.uk',
+  'devtracker.dfid.gov.uk',
+  'digitalmarketplace.service.gov.uk',
+  'eforms.homeoffice.gov.uk',
+  'electronic-visa-waiver.service.gov.uk',
+  'employmenttribunals.service.gov.uk',
+  'eu-settled-status-enquiries.service.gov.uk',
+  'faster-uk-entry.service.gov.uk',
+  'finance.manage-apprenticeships.service.gov.uk',
+  'find-and-update.company-information.service.gov.uk',
+  'findapprenticeship.service.gov.uk',
+  'find-coronavirus-support.service.gov.uk',
+  'find-employer-schemes.education.gov.uk',
+  'flood-map-for-planning.service.gov.uk',
+  'flood-warning-information.service.gov.uk',
+  'follow.company-information.service.gov.uk',
+  'gender-pay-gap.service.gov.uk',
+  'get-fishing-licence.service.gov.uk',
+  'get-information-schools.service.gov.uk',
+  'gro.gov.uk',
+  'helpforhouseholds.campaign.gov.uk',
+  'helpwithcourtfees.service.gov.uk',
+  'help-with-prison-visits.service.gov.uk',
+  'identity.company-information.service.gov.uk',
+  'identity-sandbox.company-information.service.gov.uk',
+  'import-products-animals-food-feed.service.gov.uk',
+  'lastingpowerofattorney.service.gov.uk',
+  'live.email-dvla.service.gov.uk',
+  'live.dvla-web-chat.service.gov.uk',
+  'loststolenpassport.service.gov.uk',
+  'makeaplea.service.gov.uk',
+  'managefleetvehicles.service.gov.uk',
+  'manage-apprenticeships.service.gov.uk',
+  'manage-fish-exports.service.gov.uk',
+  'manage-quota.fluorinated-gas.service.gov.uk',
+  'manage-water-abstraction-impoundment-licence.service.gov.uk',
+  'match.redundancy-payments.service.gov.uk',
+  'mot-testing.service.gov.uk',
+  'nominate-uk-honour.service.gov.uk',
+  'notice.redundancy-payments.service.gov.uk',
+  'passport.service.gov.uk',
+  'paydvlafine.service.gov.uk',
+  'payments.service.gov.uk',
+  'publish-payment-practices.service.gov.uk',
+  'queens-awards-enterprise.service.gov.uk',
+  'recruit.manage-apprenticeships.service.gov.uk',
+  'register.fluorinated-gas.service.gov.uk',
+  'register-trailer.service.gov.uk',
+  'register.ozone-depleting-substances.service.gov.uk',
+  'registertovote.service.gov.uk',
+  'register-vehicle.service.gov.uk',
+  'registers.service.gov.uk',
+  'reminders.mot-testing.service.gov.uk',
+  'renewable-heat-calculator.service.gov.uk',
+  'reply-jury-summons.service.gov.uk',
+  'report-director-conduct.service.gov.uk',
+  'report.fluorinated-gas.service.gov.uk',
+  'report.ozone-depleting-substances.service.gov.uk',
+  'right-to-rent.homeoffice.gov.uk',
+  'right-to-work.service.gov.uk',
+  'ruralpayments.service.gov.uk',
+  'schools-financial-benchmarking.service.gov.uk',
+  'secured.studentfinanceni.co.uk',
+  'secured.studentfinancewales.co.uk',
+  'selfservice.payments.service.gov.uk',
+  'send-money-to-prisoner.service.gov.uk',
+  'signin.service.gov.uk',
+  'sorn.service.gov.uk',
+  'staff.helpwithcourtfees.service.gov.uk',
+  'student-finance.service.gov.uk',
+  'tax.service.gov.uk',
+  'teacherservices.education.gov.uk',
+  'teaching-vacancies.service.gov.uk',
+  'to-visit-or-stay-in-the-uk.homeoffice.gov.uk',
+  'trade-tariff.service.gov.uk',
+  'tribunal-response.employmenttribunals.service.gov.uk',
+  'ukri.org',
+  'update-student-loan-employment-details.service.gov.uk',
+  'vehicle-operator-licensing.service.gov.uk',
+  'vehicleenquiry.service.gov.uk',
+  'viewdrivingrecord.service.gov.uk',
+  'view-and-prove-your-rights.homeoffice.gov.uk',
+  'view-immigration-status.service.gov.uk',
+  'visa-address-update.service.gov.uk',
+  'visas-immigration.service.gov.uk',
+  'your-defra-account.defra.gov.uk'
+]
diff --git a/app/assets/javascripts/govuk_publishing_components/dependencies.js b/app/assets/javascripts/govuk_publishing_components/dependencies.js
index 9b72158132..89522ce906 100644
--- a/app/assets/javascripts/govuk_publishing_components/dependencies.js
+++ b/app/assets/javascripts/govuk_publishing_components/dependencies.js
@@ -6,4 +6,13 @@
 
 document.addEventListener('DOMContentLoaded', function () {
   window.GOVUK.modules.start()
+
+  // if statements ensure these functions don't execute during testing
+  if (typeof window.GOVUK.analyticsGa4.vars === 'undefined') {
+    window.GOVUK.loadAnalytics.loadGa4()
+  }
+
+  if (typeof window.GOVUK.analyticsInit === 'undefined') {
+    window.GOVUK.loadAnalytics.loadUa()
+  }
 })
diff --git a/app/assets/javascripts/govuk_publishing_components/load-analytics.js b/app/assets/javascripts/govuk_publishing_components/load-analytics.js
new file mode 100644
index 0000000000..1b8110f97c
--- /dev/null
+++ b/app/assets/javascripts/govuk_publishing_components/load-analytics.js
@@ -0,0 +1,113 @@
+//= require govuk_publishing_components/analytics
+//= require govuk_publishing_components/analytics-ga4
+//= require govuk_publishing_components/analytics/linked-domains
+
+window.GOVUK.loadAnalytics = {
+  productionDomains: [
+    'www.gov.uk',
+    'www-origin.publishing.service.gov.uk'
+  ],
+  stagingDomains: [
+    'www.staging.publishing.service.gov.uk',
+    'www-origin.staging.publishing.service.gov.uk'
+  ],
+  integrationDomains: [
+    'www.integration.publishing.service.gov.uk',
+    'www-origin.integration.publishing.service.gov.uk'
+  ],
+  developmentDomains: [
+    'localhost', '127.0.0.1', '0.0.0.0'
+  ],
+
+  // For Universal Analytics' cross domain tracking. linkedDomains is defined by the require statement at the top of the file.
+  linkedDomains: window.GOVUK.analytics.linkedDomains,
+
+  ga4EnvironmentVariables: {
+    // initialiseGA4 is used to enable/disable GA4 on specific environments
+    production: {
+      initialiseGA4: true
+    },
+    staging: {
+      initialiseGA4: true,
+      auth: 'oJWs562CxSIjZKn_GlB5Bw',
+      preview: 'env-5'
+    },
+    integration: {
+      initialiseGA4: true,
+      auth: 'C7iYdcsOlYgGmiUJjZKrHQ',
+      preview: 'env-4'
+    },
+    development: {
+      initialiseGA4: true,
+      auth: 'bRiZ-jiEHtw6hHpGd6dF9w',
+      preview: 'env-3'
+    }
+  },
+
+  loadUa: function (currentDomain) {
+    currentDomain = currentDomain || window.location.hostname
+
+    // Universal Analytics variables
+    window.GOVUK.analyticsVars = window.GOVUK.analyticsVars || {}
+    window.GOVUK.analyticsVars.primaryLinkedDomains = ['account.gov.uk']
+    window.GOVUK.analyticsVars.linkedDomains = this.linkedDomains
+    window.GOVUK.analyticsVars.gaProperty = 'UA-UNSET'
+    window.GOVUK.analyticsVars.gaPropertyCrossDomain = 'UA-UNSET'
+
+    if (this.arrayContains(currentDomain, this.productionDomains)) {
+      window.GOVUK.analyticsVars.gaProperty = 'UA-26179049-1'
+      window.GOVUK.analyticsVars.gaPropertyCrossDomain = 'UA-145652997-1'
+    } else if (this.arrayContains(currentDomain, this.stagingDomains)) {
+      window.GOVUK.analyticsVars.gaProperty = 'UA-26179049-20'
+      window.GOVUK.analyticsVars.gaPropertyCrossDomain = 'UA-145652997-1'
+    } else if (this.arrayContains(currentDomain, this.integrationDomains)) {
+      window.GOVUK.analyticsVars.gaProperty = 'UA-26179049-22'
+      window.GOVUK.analyticsVars.gaPropertyCrossDomain = 'UA-145652997-1'
+    }
+
+    // Load universal analytics
+    if (typeof window.GOVUK.analyticsInit !== 'undefined') {
+      window.GOVUK.analyticsInit()
+    }
+  },
+
+  loadGa4: function (currentDomain) {
+    currentDomain = currentDomain || window.location.hostname
+    var environment = ''
+
+    // Categorise current environment
+    if (this.arrayContains(currentDomain, this.productionDomains)) {
+      environment = 'production'
+    } else if (this.arrayContains(currentDomain, this.stagingDomains)) {
+      environment = 'staging'
+    } else if (this.arrayContains(currentDomain, this.integrationDomains)) {
+      environment = 'integration'
+    } else if (this.arrayContains(currentDomain, this.developmentDomains) || currentDomain.indexOf('.dev.gov.uk') !== -1) {
+      environment = 'development'
+    }
+
+    // If we recognise the environment (i.e. the string isn't empty), load in GA4
+    if (environment) {
+      // If analytics-ga4.js exists and our detected environment has 'initialiseGA4' set to true, load GA4.
+      if (typeof window.GOVUK.analyticsGa4.init !== 'undefined' && this.ga4EnvironmentVariables[environment].initialiseGA4) {
+        window.GOVUK.analyticsGa4 = window.GOVUK.analyticsGa4 || {}
+        window.GOVUK.analyticsGa4.vars = window.GOVUK.analyticsGa4.vars || {}
+        window.GOVUK.analyticsGa4.vars.id = 'GTM-MG7HG5W'
+        window.GOVUK.analyticsGa4.vars.auth = this.ga4EnvironmentVariables[environment].auth
+        window.GOVUK.analyticsGa4.vars.preview = this.ga4EnvironmentVariables[environment].preview
+        window.GOVUK.analyticsGa4.vars.environment = environment // Used for testing and debugging
+
+        window.GOVUK.analyticsGa4.vars.gem_version = 'not found'
+        var gemMeta = document.querySelector('meta[name="govuk:components_gem_version"]')
+        if (gemMeta) {
+          window.GOVUK.analyticsGa4.vars.gem_version = gemMeta.getAttribute('content')
+        }
+        window.GOVUK.analyticsGa4.init()
+      }
+    }
+  },
+
+  arrayContains: function (valueToFind, array) {
+    return array.indexOf(valueToFind) !== -1
+  }
+}
diff --git a/app/views/govuk_publishing_components/components/_layout_for_public.html.erb b/app/views/govuk_publishing_components/components/_layout_for_public.html.erb
index 4e56a17f0f..f6d3496e0e 100644
--- a/app/views/govuk_publishing_components/components/_layout_for_public.html.erb
+++ b/app/views/govuk_publishing_components/components/_layout_for_public.html.erb
@@ -58,6 +58,7 @@
           "lux-reporter-script": path_to_javascript("govuk_publishing_components/vendor/lux/lux-reporter")
         }
       } %>
+    <%= javascript_include_tag "govuk_publishing_components/load-analytics" %>
 
     <%= csrf_meta_tags %>
 
@@ -78,6 +79,9 @@
     <% # The default og:image is added below :head so that scrapers see any custom metatags first, and this is just a fallback %>
     <meta property="og:image" content="<%= asset_path "govuk-opengraph-image.png" %>">
 
+    <% # Used for Google Analytics 4 debugging %>
+    <meta name="govuk:components_gem_version" content="<%= GovukPublishingComponents::VERSION %>" />
+
     <%= yield :head %>
   </head>
   <%= tag.body class: body_css_classes do %>
diff --git a/docs/analytics/analytics.md b/docs/analytics/analytics.md
index d867263d42..b31394c04e 100644
--- a/docs/analytics/analytics.md
+++ b/docs/analytics/analytics.md
@@ -170,7 +170,7 @@ named tracker, and sessions will persist to the other domain.
 
 Once a service starts sending analytics data to the shared GA property and has configured their system to include `www.gov.uk` in their cross domain linking, we must also configure `www.gov.uk` to include their domain in our cross linker configuration.
 
-Add the domain of the service to [`init.js.erb`](https://github.com/alphagov/static/blob/main/app/assets/javascripts/analytics.js.erb).
+Add the domain of the service to [linked-domains.js](https://github.com/alphagov/govuk_publishing_components/tree/main/app/assets/javascripts/govuk_publishing_components/analytics/linked-domains.js).
 
 Here's an [example of an earlier PR](https://github.com/alphagov/static/pull/1845) to do this.
 
diff --git a/docs/load-analytics.md b/docs/load-analytics.md
new file mode 100644
index 0000000000..63f883d163
--- /dev/null
+++ b/docs/load-analytics.md
@@ -0,0 +1,17 @@
+# Loading analytics into our applications
+
+For analytics tracking, each environment (production, staging, integration, development) uses different environment variables. These environment variables are used to determine which dashboard analytics data is sent to. This is useful to us for testing and debugging, as we can test our analytics in isolated environments. Therefore, we want to be able to set different environment variables depending on which environment we are in. This needs to happen before our analytics code is initialised, so `load-analytics.js` executes before our analytics code is run.
+
+Therefore, `load-analytics.js` has been written to do the following:
+
+1. Grab the current domain that the code is running on using `window.location.hostname`.
+2. Determine the environment you are on by comparing your domain against hardcoded categorised domains.
+3. Set the correct environment variables for both Universal Analytics, and Google Analytics 4, depending on the environment you are on. These are also hardcoded now.
+4. Kick off the initialisation of analytics by running their respective `init()` functions, which will then run the `ga4-core.js` code and the UA tracking initialisation code.
+5. The `ga4-core.js` / UA code then makes use of these environment variables. It can access them as they are set on the JavaScript `window` object.
+
+The Google Analytics 4 environment variables are:
+
+- `id` - this is the Google Tag Manager ID used to identify our organisation so that analytics data is sent to the right account.
+- `preview` - this is an optional variable that is used to determine what GTM environment the analytics data is sent to. If this is empty, analytics data is sent to the production dashboard. If you wanted to have your integration analytics to an 'integration' dashboard, you would populate this variable with the relevant value.
+- `auth` - this is used to authenticate analytics data being sent to another dashboard, such as an 'integration' dashboard. This can be determined through the browser so they're not classified as secret.
\ No newline at end of file
diff --git a/spec/javascripts/govuk_publishing_components/load-analytics.spec.js b/spec/javascripts/govuk_publishing_components/load-analytics.spec.js
new file mode 100644
index 0000000000..af0ce479b7
--- /dev/null
+++ b/spec/javascripts/govuk_publishing_components/load-analytics.spec.js
@@ -0,0 +1,190 @@
+/* eslint-env jasmine */
+
+var expected
+var savedUaVars
+var savedGa4Vars
+
+describe('Analytics loading', function () {
+  beforeAll(function () {
+    savedUaVars = window.GOVUK.extendObject(window.GOVUK.analyticsVars)
+    window.GOVUK.analyticsGa4 = window.GOVUK.analyticsGa4 || {}
+    savedGa4Vars = window.GOVUK.extendObject(window.GOVUK.analyticsGa4.vars)
+  })
+
+  afterAll(function () {
+    window.GOVUK.analyticsGa4.vars = savedGa4Vars
+    window.GOVUK.analyticsVars = savedUaVars
+  })
+
+  describe('for GA4', function () {
+    beforeEach(function () {
+      window.GOVUK.analyticsGa4.vars = null
+      expected = {
+        id: 'GTM-MG7HG5W',
+        auth: undefined,
+        preview: undefined,
+        environment: 'production',
+        gem_version: 'not found'
+      }
+    })
+
+    it('loads GA4 on production domains', function () {
+      var domains = [
+        'www.gov.uk',
+        'www-origin.publishing.service.gov.uk'
+      ]
+
+      for (var i = 0; i < domains.length; i++) {
+        window.GOVUK.analyticsGa4.vars = null
+        var domain = domains[i]
+        window.GOVUK.loadAnalytics.loadGa4(domain)
+        expect(window.GOVUK.analyticsGa4.vars.environment).toEqual('production')
+      }
+    })
+
+    it('loads GA4 on staging domains', function () {
+      var domains = [
+        'www.staging.publishing.service.gov.uk',
+        'www.staging.publishing.service.gov.uk',
+        'www-origin.staging.publishing.service.gov.uk'
+      ]
+      for (var i = 0; i < domains.length; i++) {
+        window.GOVUK.analyticsGa4.vars = null
+        var domain = domains[i]
+        window.GOVUK.loadAnalytics.loadGa4(domain)
+        expect(window.GOVUK.analyticsGa4.vars.environment).toEqual('staging')
+      }
+    })
+
+    it('loads GA4 on integration domains', function () {
+      var domains = [
+        'www.integration.publishing.service.gov.uk',
+        'www.integration.publishing.service.gov.uk',
+        'www-origin.integration.publishing.service.gov.uk'
+      ]
+
+      for (var i = 0; i < domains.length; i++) {
+        window.GOVUK.analyticsGa4.vars = null
+        var domain = domains[i]
+        window.GOVUK.loadAnalytics.loadGa4(domain)
+        expect(window.GOVUK.analyticsGa4.vars.environment).toEqual('integration')
+      }
+    })
+
+    it('loads GA4 on development domains', function () {
+      var domains = [
+        'localhost', '127.0.0.1', '0.0.0.0', 'static.dev.gov.uk'
+      ]
+
+      for (var i = 0; i < domains.length; i++) {
+        window.GOVUK.analyticsGa4.vars = null
+        var domain = domains[i]
+        window.GOVUK.loadAnalytics.loadGa4(domain)
+        expect(window.GOVUK.analyticsGa4.vars.environment).toEqual('development')
+      }
+    })
+
+    it('ignores loading GA4 on unrecognised domains', function () {
+      var domains = [
+        'www.nationalarchives.gov.uk'
+      ]
+
+      for (var i = 0; i < domains.length; i++) {
+        window.GOVUK.analyticsGa4.vars = null
+        var domain = domains[i]
+        window.GOVUK.loadAnalytics.loadGa4(domain)
+        expect(window.GOVUK.analyticsGa4.vars).toEqual(null)
+      }
+    })
+
+    it('sets the correct production variables', function () {
+      window.GOVUK.loadAnalytics.loadGa4('www.gov.uk')
+      delete window.GOVUK.analyticsGa4.vars.internalDomains
+      expect(window.GOVUK.analyticsGa4.vars).toEqual(expected)
+    })
+
+    it('sets the correct staging variables', function () {
+      expected.environment = 'staging'
+      expected.auth = 'oJWs562CxSIjZKn_GlB5Bw'
+      expected.preview = 'env-5'
+
+      window.GOVUK.loadAnalytics.loadGa4('www.staging.publishing.service.gov.uk')
+      delete window.GOVUK.analyticsGa4.vars.internalDomains
+      expect(window.GOVUK.analyticsGa4.vars).toEqual(expected)
+    })
+
+    it('sets the correct integration variables', function () {
+      expected.environment = 'integration'
+      expected.auth = 'C7iYdcsOlYgGmiUJjZKrHQ'
+      expected.preview = 'env-4'
+      window.GOVUK.loadAnalytics.loadGa4('www.integration.publishing.service.gov.uk')
+      delete window.GOVUK.analyticsGa4.vars.internalDomains
+      expect(window.GOVUK.analyticsGa4.vars).toEqual(expected)
+    })
+
+    it('sets the correct development variables', function () {
+      expected.environment = 'development'
+      expected.auth = 'bRiZ-jiEHtw6hHpGd6dF9w'
+      expected.preview = 'env-3'
+      window.GOVUK.loadAnalytics.loadGa4('localhost')
+      delete window.GOVUK.analyticsGa4.vars.internalDomains
+      expect(window.GOVUK.analyticsGa4.vars).toEqual(expected)
+    })
+
+    it('doesnt load GA4 variables if initialiseGA4 is set to false', function () {
+      window.GOVUK.loadAnalytics.ga4EnvironmentVariables.production.initialiseGA4 = false
+      window.GOVUK.loadAnalytics.loadGa4('www.gov.uk')
+      expect(window.GOVUK.analyticsGa4.vars).toEqual(null)
+      window.GOVUK.loadAnalytics.ga4EnvironmentVariables.production.initialiseGA4 = true
+    })
+  })
+
+  describe('for UA', function () {
+    beforeEach(function () {
+      window.GOVUK.analyticsVars = null
+      expected = {
+        gaPropertyCrossDomain: 'UA-145652997-1',
+        primaryLinkedDomains: ['account.gov.uk'],
+        linkedDomains: ['hello', 'world']
+      }
+      window.GOVUK.loadAnalytics.linkedDomains = ['hello', 'world']
+    })
+
+    it('loads the correct UA values on production', function () {
+      expected.gaProperty = 'UA-26179049-1'
+      window.GOVUK.loadAnalytics.loadUa('www.gov.uk')
+      expect(window.GOVUK.analyticsVars).toEqual(expected)
+    })
+
+    it('loads the correct UA values on staging', function () {
+      expected.gaProperty = 'UA-26179049-20'
+      window.GOVUK.loadAnalytics.loadUa('www.staging.publishing.service.gov.uk')
+      expect(window.GOVUK.analyticsVars).toEqual(expected)
+    })
+
+    it('loads the correct UA values on integration', function () {
+      expected.gaProperty = 'UA-26179049-22'
+      window.GOVUK.loadAnalytics.loadUa('www.integration.publishing.service.gov.uk')
+      expect(window.GOVUK.analyticsVars).toEqual(expected)
+    })
+
+    it('loads the correct UA values on development', function () {
+      expected.gaProperty = 'UA-UNSET'
+      expected.gaPropertyCrossDomain = 'UA-UNSET'
+      window.GOVUK.loadAnalytics.loadUa('localhost')
+      expect(window.GOVUK.analyticsVars).toEqual(expected)
+    })
+
+    it('loads the correct UA values on unrecognised domains', function () {
+      expected.gaProperty = 'UA-UNSET'
+      expected.gaPropertyCrossDomain = 'UA-UNSET'
+      window.GOVUK.loadAnalytics.loadUa('www.nationalarchives.gov.uk')
+      expect(window.GOVUK.analyticsVars).toEqual(expected)
+    })
+  })
+
+  it('finds values in arrays correctly', function () {
+    expect(window.GOVUK.loadAnalytics.arrayContains('dog', ['cat', 'dog'])).toEqual(true)
+    expect(window.GOVUK.loadAnalytics.arrayContains('dog', ['cat'])).toEqual(false)
+  })
+})
diff --git a/spec/javascripts/helpers/SpecHelper.js b/spec/javascripts/helpers/SpecHelper.js
index 59a9ed60b2..93bfe5cb7e 100644
--- a/spec/javascripts/helpers/SpecHelper.js
+++ b/spec/javascripts/helpers/SpecHelper.js
@@ -22,13 +22,19 @@ var resetCookies = function () {
   document.cookie.split(';').forEach(function (c) { document.cookie = c.replace(/^ +/, '').replace(/=.*/, '=;expires=' + new Date().toUTCString() + ';path=/') })
 }
 
+var savedUaVars
+
 // external-link-tracker.js adds a click event to the body for matching links
 // gets called once in production but multiple times in testing e.g. in static-analytics-spec
 // every time it does `new GOVUK.StaticAnalytics()` so need to remove this using .off()
 beforeEach(function () {
   $('body').off()
+
+// load-analytics.js modifies the universal analytics vars, so we need to ensure they are reset each time.
+  savedUaVars = window.GOVUK.extendObject(window.GOVUK.analyticsVars)
 })
 
 afterEach(function () {
   resetCookies()
+  window.GOVUK.analyticsVars = savedUaVars
 })
diff --git a/spec/support/jasmine-browser.json b/spec/support/jasmine-browser.json
index b877733e85..7eea0fd0fc 100644
--- a/spec/support/jasmine-browser.json
+++ b/spec/support/jasmine-browser.json
@@ -5,6 +5,7 @@
     "govuk_publishing_components/all_components-*.js",
     "govuk_publishing_components/modules-*.js",
     "govuk_publishing_components/analytics-*.js",
+    "govuk_publishing_components/load-analytics-*.js",
     "govuk_publishing_components/vendor/lux/lux-measurer-*.js",
     "component_guide/accessibility-test-*.js",
     "component_guide/filter-components-*.js"