diff --git a/ghost/core/core/frontend/src/member-attribution/member-attribution.js b/ghost/core/core/frontend/src/member-attribution/member-attribution.js
index 6cd8c16eebc..72223d661f2 100644
--- a/ghost/core/core/frontend/src/member-attribution/member-attribution.js
+++ b/ghost/core/core/frontend/src/member-attribution/member-attribution.js
@@ -76,6 +76,8 @@ const LIMIT = 15;
         let sourceParam;
         let utmSourceParam;
         let utmMediumParam;
+        let referrerSource;
+
         try {
             // Fetch source/medium from query param
             const url = new URL(window.location.href);
@@ -83,11 +85,23 @@ const LIMIT = 15;
             sourceParam = url.searchParams.get('source');
             utmSourceParam = url.searchParams.get('utm_source');
             utmMediumParam = url.searchParams.get('utm_medium');
+
+            referrerSource = refParam || sourceParam || utmSourceParam || null;
+
+            // if referrerSource is not set, check to see if the url contains a hash like ghost.org/#/portal/signup?ref=ghost and pull the ref from the hash
+            if (!referrerSource && url.hash && url.hash.includes('#/portal')) {
+                const hashUrl = new URL(window.location.href.replace('/#/portal', ''));
+                refParam = hashUrl.searchParams.get('ref');
+                sourceParam = hashUrl.searchParams.get('source');
+                utmSourceParam = hashUrl.searchParams.get('utm_source');
+                utmMediumParam = hashUrl.searchParams.get('utm_medium');
+    
+                referrerSource = refParam || sourceParam || utmSourceParam || null;
+            }
         } catch (e) {
             console.error('[Member Attribution] Parsing referrer from querystring failed', e);
         }
 
-        const referrerSource = refParam || sourceParam || utmSourceParam || null;
         const referrerMedium = utmMediumParam || null;
         const referrerUrl = window.document.referrer || null;
 
diff --git a/ghost/core/test/e2e-server/services/member-attribution.test.js b/ghost/core/test/e2e-server/services/member-attribution.test.js
index f4e25e8fcbc..4a3e8099956 100644
--- a/ghost/core/test/e2e-server/services/member-attribution.test.js
+++ b/ghost/core/test/e2e-server/services/member-attribution.test.js
@@ -400,5 +400,25 @@ describe('Member Attribution Service', function () {
                 referrerUrl: null
             }));
         });
+
+        it('resolves Portal signup URLs', async function () {
+            // NOTE: We cannot test the actual hash URL here; the attribution below is what is receieved when navigating to /#/portal/signup?ref=ghost
+            // TODO: We don't appear to have tests for parsing URLs for params.
+            const attribution = await memberAttributionService.service.getAttribution([
+                {
+                    path: '/',
+                    time: Date.now(),
+                    referrerSource: 'casper'
+                }
+            ]);
+            attribution.should.match(({
+                id: null,
+                url: '/',
+                type: 'url',
+                referrerSource: 'casper',
+                referrerMedium: null,
+                referrerUrl: null
+            }));
+        });
     });
-});
+});
\ No newline at end of file