diff --git a/app/routes/crate/settings/new-trusted-publisher.js b/app/routes/crate/settings/new-trusted-publisher.js
index 259cad18732..de0005470f9 100644
--- a/app/routes/crate/settings/new-trusted-publisher.js
+++ b/app/routes/crate/settings/new-trusted-publisher.js
@@ -5,4 +5,27 @@ export default class NewTrustedPublisherRoute extends Route {
     let crate = this.modelFor('crate');
     return { crate };
   }
+
+  setupController(controller, model) {
+    super.setupController(controller, model);
+
+    controller.repositoryOwner = '';
+    controller.repositoryName = '';
+    controller.workflowFilename = '';
+    controller.environment = '';
+
+    let repository = model.crate.repository;
+    if (repository && repository.startsWith('https://github.com/')) {
+      try {
+        let url = new URL(repository);
+        let pathParts = url.pathname.slice(1).split('/');
+        if (pathParts.length >= 2) {
+          controller.repositoryOwner = pathParts[0];
+          controller.repositoryName = pathParts[1].replace(/.git$/, '');
+        }
+      } catch {
+        // ignore malformed URLs
+      }
+    }
+  }
 }
diff --git a/e2e/routes/crate/settings/new-trusted-publisher.spec.ts b/e2e/routes/crate/settings/new-trusted-publisher.spec.ts
index 5d5497d3df4..d69fcf81b0d 100644
--- a/e2e/routes/crate/settings/new-trusted-publisher.spec.ts
+++ b/e2e/routes/crate/settings/new-trusted-publisher.spec.ts
@@ -182,4 +182,67 @@ test.describe('Route | crate.settings.new-trusted-publisher', { tag: '@routes' }
     // Check that we're redirected back to the crate settings page
     await expect(page).toHaveURL(`/crates/${crate.name}/settings`);
   });
+
+  test.describe('prefill', () => {
+    const testCases = [
+      {
+        name: 'simple https',
+        url: 'https://github.com/rust-lang/crates.io',
+        owner: 'rust-lang',
+        repo: 'crates.io',
+      },
+      {
+        name: 'with .git suffix',
+        url: 'https://github.com/rust-lang/crates.io.git',
+        owner: 'rust-lang',
+        repo: 'crates.io',
+      },
+      {
+        name: 'with extra path segments',
+        url: 'https://github.com/Byron/google-apis-rs/tree/main/gen/privateca1',
+        owner: 'Byron',
+        repo: 'google-apis-rs',
+      },
+      {
+        name: 'non-github url',
+        url: 'https://gitlab.com/rust-lang/crates.io',
+        owner: '',
+        repo: '',
+      },
+      {
+        name: 'not a url',
+        url: 'not a url',
+        owner: '',
+        repo: '',
+      },
+      {
+        name: 'empty string',
+        url: '',
+        owner: '',
+        repo: '',
+      },
+      {
+        name: 'null',
+        url: null,
+        owner: '',
+        repo: '',
+      },
+    ];
+
+    for (const { name, url, owner, repo } of testCases) {
+      test(name, async ({ msw, page }) => {
+        let { crate } = await prepare(msw);
+
+        msw.db.crate.update({
+          where: { id: { equals: crate.id } },
+          data: { repository: url },
+        });
+
+        await page.goto(`/crates/${crate.name}/settings/new-trusted-publisher`);
+
+        await expect(page.locator('[data-test-repository-owner]')).toHaveValue(owner);
+        await expect(page.locator('[data-test-repository-name]')).toHaveValue(repo);
+      });
+    }
+  });
 });
diff --git a/tests/routes/crate/settings/new-trusted-publisher-test.js b/tests/routes/crate/settings/new-trusted-publisher-test.js
index 415c79f122c..157231163ae 100644
--- a/tests/routes/crate/settings/new-trusted-publisher-test.js
+++ b/tests/routes/crate/settings/new-trusted-publisher-test.js
@@ -190,4 +190,66 @@ module('Route | crate.settings.new-trusted-publisher', hooks => {
     // Check that we're redirected back to the crate settings page
     assert.strictEqual(currentURL(), `/crates/${crate.name}/settings`);
   });
+
+  module('prefill', function () {
+    let testCases = [
+      {
+        name: 'simple https',
+        url: 'https://github.com/rust-lang/crates.io',
+        owner: 'rust-lang',
+        repo: 'crates.io',
+      },
+      {
+        name: 'with .git suffix',
+        url: 'https://github.com/rust-lang/crates.io.git',
+        owner: 'rust-lang',
+        repo: 'crates.io',
+      },
+      {
+        name: 'with extra path segments',
+        url: 'https://github.com/Byron/google-apis-rs/tree/main/gen/privateca1',
+        owner: 'Byron',
+        repo: 'google-apis-rs',
+      },
+      {
+        name: 'non-github url',
+        url: 'https://gitlab.com/rust-lang/crates.io',
+        owner: '',
+        repo: '',
+      },
+      {
+        name: 'not a url',
+        url: 'not a url',
+        owner: '',
+        repo: '',
+      },
+      {
+        name: 'empty string',
+        url: '',
+        owner: '',
+        repo: '',
+      },
+      {
+        name: 'null',
+        url: null,
+        owner: '',
+        repo: '',
+      },
+    ];
+
+    for (let { name, url, owner, repo } of testCases) {
+      test(name, async function (assert) {
+        let { crate } = prepare(this);
+        this.db.crate.update({
+          where: { id: { equals: crate.id } },
+          data: { repository: url },
+        });
+
+        await visit(`/crates/${crate.name}/settings/new-trusted-publisher`);
+
+        assert.dom('[data-test-repository-owner]').hasValue(owner);
+        assert.dom('[data-test-repository-name]').hasValue(repo);
+      });
+    }
+  });
 });