diff --git a/site/src/pages/OrganizationSettingsPage/CustomRolesPage/CustomRolesPage.tsx b/site/src/pages/OrganizationSettingsPage/CustomRolesPage/CustomRolesPage.tsx
index 546408bb87d8f..03174f8bb79dc 100644
--- a/site/src/pages/OrganizationSettingsPage/CustomRolesPage/CustomRolesPage.tsx
+++ b/site/src/pages/OrganizationSettingsPage/CustomRolesPage/CustomRolesPage.tsx
@@ -3,6 +3,7 @@ import { useMutation, useQuery, useQueryClient } from "react-query";
 import { useParams } from "react-router";
 import { toast } from "sonner";
 import { getErrorDetail, getErrorMessage } from "#/api/errors";
+import { updateOrganization } from "#/api/queries/organizations";
 import { deleteOrganizationRole, organizationRoles } from "#/api/queries/roles";
 import type { Role } from "#/api/typesGenerated";
 import { DeleteDialog } from "#/components/Dialogs/DeleteDialog/DeleteDialog";
@@ -12,6 +13,7 @@ import {
 	SettingsHeaderDescription,
 	SettingsHeaderTitle,
 } from "#/components/SettingsHeader/SettingsHeader";
+import { useDashboard } from "#/modules/dashboard/useDashboard";
 import { useFeatureVisibility } from "#/modules/dashboard/useFeatureVisibility";
 import { useOrganizationSettings } from "#/modules/management/OrganizationSettingsLayout";
 import { RequirePermission } from "#/modules/permissions/RequirePermission";
@@ -25,6 +27,10 @@ const CustomRolesPage: FC = () => {
 		organization: string;
 	};
 	const { organization, organizationPermissions } = useOrganizationSettings();
+	const { experiments, entitlements } = useDashboard();
+	const defaultRolesEnabled = experiments.includes("minimum-implicit-member");
+	const defaultRolesEntitled =
+		entitlements.features.multiple_organizations.enabled;
 
 	const [roleToDelete, setRoleToDelete] = useState<Role>();
 
@@ -39,6 +45,9 @@ const CustomRolesPage: FC = () => {
 	const deleteRoleMutation = useMutation(
 		deleteOrganizationRole(queryClient, organizationName),
 	);
+	const updateOrganizationMutation = useMutation(
+		updateOrganization(queryClient),
+	);
 
 	useEffect(() => {
 		if (organizationRolesQuery.error) {
@@ -80,13 +89,33 @@ const CustomRolesPage: FC = () => {
 				</div>
 
 				<CustomRolesPageView
+					organization={organization}
 					builtInRoles={builtInRoles}
 					customRoles={customRoles}
 					onDeleteRole={setRoleToDelete}
 					canCreateOrgRole={organizationPermissions?.createOrgRoles ?? false}
 					canUpdateOrgRole={organizationPermissions?.updateOrgRoles ?? false}
 					canDeleteOrgRole={organizationPermissions?.deleteOrgRoles ?? false}
+					canEditDefaultRoles={organizationPermissions?.editSettings ?? false}
 					isCustomRolesEnabled={isCustomRolesEnabled}
+					defaultRolesEnabled={defaultRolesEnabled}
+					defaultRolesEntitled={defaultRolesEntitled}
+					availableOrgRoles={organizationRolesQuery.data}
+					isUpdatingDefaultRoles={updateOrganizationMutation.isPending}
+					onUpdateDefaultRoles={async (roles) => {
+						try {
+							await updateOrganizationMutation.mutateAsync({
+								organizationId: organization.id,
+								req: { default_org_member_roles: roles },
+							});
+							toast.success("Default roles updated.");
+						} catch (error) {
+							toast.error(
+								getErrorMessage(error, "Failed to update default roles."),
+								{ description: getErrorDetail(error) },
+							);
+						}
+					}}
 				/>
 
 				<DeleteDialog
diff --git a/site/src/pages/OrganizationSettingsPage/CustomRolesPage/CustomRolesPageView.stories.tsx b/site/src/pages/OrganizationSettingsPage/CustomRolesPage/CustomRolesPageView.stories.tsx
index 18d40aac91dac..a66529ff24883 100644
--- a/site/src/pages/OrganizationSettingsPage/CustomRolesPage/CustomRolesPageView.stories.tsx
+++ b/site/src/pages/OrganizationSettingsPage/CustomRolesPage/CustomRolesPageView.stories.tsx
@@ -1,17 +1,59 @@
 import type { Meta, StoryObj } from "@storybook/react-vite";
+import { action } from "storybook/actions";
+import { expect, userEvent, within } from "storybook/test";
+import type { AssignableRoles } from "#/api/typesGenerated";
 import {
+	MockOrganization,
 	MockOrganizationAuditorRole,
 	MockRoleWithOrgPermissions,
 } from "#/testHelpers/entities";
 import { CustomRolesPageView } from "./CustomRolesPageView";
 
+const mockOrgRoles: AssignableRoles[] = [
+	{
+		name: "organization-workspace-access",
+		display_name: "Organization Workspace Access",
+		organization_id: MockOrganization.id,
+		site_permissions: [],
+		organization_permissions: [],
+		organization_member_permissions: [],
+		user_permissions: [],
+		assignable: true,
+		built_in: true,
+	},
+	{
+		name: "organization-admin",
+		display_name: "Organization Admin",
+		organization_id: MockOrganization.id,
+		site_permissions: [],
+		organization_permissions: [],
+		organization_member_permissions: [],
+		user_permissions: [],
+		assignable: true,
+		built_in: true,
+	},
+	{
+		name: "agents-access",
+		display_name: "Agents Access",
+		organization_id: MockOrganization.id,
+		site_permissions: [],
+		organization_permissions: [],
+		organization_member_permissions: [],
+		user_permissions: [],
+		assignable: true,
+		built_in: true,
+	},
+];
+
 const meta: Meta<typeof CustomRolesPageView> = {
 	title: "pages/OrganizationCustomRolesPage",
 	component: CustomRolesPageView,
 	args: {
+		organization: MockOrganization,
 		builtInRoles: [MockRoleWithOrgPermissions],
 		customRoles: [MockRoleWithOrgPermissions],
 		canCreateOrgRole: true,
+		canEditDefaultRoles: true,
 		isCustomRolesEnabled: true,
 	},
 };
@@ -66,3 +108,98 @@ export const EmptyTableUserWithPermission: Story = {
 		customRoles: [],
 	},
 };
+
+export const DefaultRolesHidden: Story = {
+	args: {
+		defaultRolesEnabled: false,
+		availableOrgRoles: mockOrgRoles,
+		onUpdateDefaultRoles: async () => {
+			action("onUpdateDefaultRoles")();
+		},
+	},
+	play: async ({ canvasElement }) => {
+		const body = within(canvasElement.ownerDocument.body);
+		expect(body.queryByText("Default Roles")).toBeNull();
+	},
+};
+
+export const DefaultRolesEnabled: Story = {
+	args: {
+		defaultRolesEnabled: true,
+		defaultRolesEntitled: true,
+		availableOrgRoles: mockOrgRoles,
+		onUpdateDefaultRoles: async () => {
+			action("onUpdateDefaultRoles")();
+		},
+	},
+};
+
+export const DefaultRolesNotEntitled: Story = {
+	args: {
+		defaultRolesEnabled: true,
+		defaultRolesEntitled: false,
+		availableOrgRoles: mockOrgRoles,
+		onUpdateDefaultRoles: async () => {
+			action("onUpdateDefaultRoles")();
+		},
+	},
+	play: async ({ canvasElement }) => {
+		const body = within(canvasElement.ownerDocument.body);
+		const editButton = await body.findByRole("button", {
+			name: /edit default roles/i,
+		});
+		expect(editButton).toBeDisabled();
+		await body.findByText(/requires a Premium license/i);
+	},
+};
+
+export const DefaultRolesEmpty: Story = {
+	args: {
+		organization: {
+			...MockOrganization,
+			default_org_member_roles: [],
+		},
+		defaultRolesEnabled: true,
+		defaultRolesEntitled: true,
+		availableOrgRoles: mockOrgRoles,
+		onUpdateDefaultRoles: async () => {
+			action("onUpdateDefaultRoles")();
+		},
+	},
+};
+
+export const DefaultRolesHiddenWithoutEditPermission: Story = {
+	args: {
+		defaultRolesEnabled: true,
+		defaultRolesEntitled: true,
+		canEditDefaultRoles: false,
+		availableOrgRoles: mockOrgRoles,
+		onUpdateDefaultRoles: async () => {
+			action("onUpdateDefaultRoles")();
+		},
+	},
+	play: async ({ canvasElement }) => {
+		const body = within(canvasElement.ownerDocument.body);
+		expect(body.queryByText("Default Roles")).toBeNull();
+	},
+};
+
+export const DefaultRolesEditDialog: Story = {
+	args: {
+		defaultRolesEnabled: true,
+		defaultRolesEntitled: true,
+		availableOrgRoles: mockOrgRoles,
+		onUpdateDefaultRoles: async () => {
+			action("onUpdateDefaultRoles")();
+		},
+	},
+	play: async ({ canvasElement }) => {
+		const user = userEvent.setup();
+		const body = within(canvasElement.ownerDocument.body);
+		const editButton = await body.findByRole("button", {
+			name: /edit default roles/i,
+		});
+		await user.click(editButton);
+		await body.findByRole("heading", { name: /edit default roles/i });
+	},
+};
diff --git a/site/src/pages/OrganizationSettingsPage/CustomRolesPage/CustomRolesPageView.tsx b/site/src/pages/OrganizationSettingsPage/CustomRolesPage/CustomRolesPageView.tsx
index db6556027eb6a..2ebe55b3aa1ba 100644
--- a/site/src/pages/OrganizationSettingsPage/CustomRolesPage/CustomRolesPageView.tsx
+++ b/site/src/pages/OrganizationSettingsPage/CustomRolesPage/CustomRolesPageView.tsx
@@ -1,7 +1,8 @@
 import { EllipsisVerticalIcon, PlusIcon } from "lucide-react";
-import type { FC } from "react";
+import { type FC, useState } from "react";
 import { Link as RouterLink, useNavigate } from "react-router";
-import type { AssignableRoles, Role } from "#/api/typesGenerated";
+import type { AssignableRoles, Organization, Role } from "#/api/typesGenerated";
+import { PremiumBadge } from "#/components/Badges/Badges";
 import { Button, Button as ShadcnButton } from "#/components/Button/Button";
 import {
 	DropdownMenu,
@@ -25,27 +26,45 @@ import {
 	TableRowSkeleton,
 } from "#/components/TableLoader/TableLoader";
 import { docs } from "#/utils/docs";
+import { DefaultRolesDialog } from "./DefaultRolesDialog";
 import { PermissionPillsList } from "./PermissionPillsList";
 
 interface CustomRolesPageViewProps {
+	organization: Organization;
 	builtInRoles: AssignableRoles[] | undefined;
 	customRoles: AssignableRoles[] | undefined;
 	onDeleteRole: (role: Role) => void;
 	canCreateOrgRole: boolean;
 	canUpdateOrgRole: boolean;
 	canDeleteOrgRole: boolean;
+	canEditDefaultRoles: boolean;
 	isCustomRolesEnabled: boolean;
+	defaultRolesEnabled?: boolean;
+	defaultRolesEntitled?: boolean;
+	availableOrgRoles?: AssignableRoles[];
+	onUpdateDefaultRoles?: (roles: string[]) => Promise<void>;
+	isUpdatingDefaultRoles?: boolean;
 }
 
 export const CustomRolesPageView: FC<CustomRolesPageViewProps> = ({
+	organization,
 	builtInRoles,
 	customRoles,
 	onDeleteRole,
 	canCreateOrgRole,
 	canUpdateOrgRole,
 	canDeleteOrgRole,
+	canEditDefaultRoles,
 	isCustomRolesEnabled,
+	defaultRolesEnabled,
+	defaultRolesEntitled,
+	availableOrgRoles,
+	onUpdateDefaultRoles,
+	isUpdatingDefaultRoles,
 }) => {
+	const showDefaultRoles =
+		defaultRolesEnabled && canEditDefaultRoles && Boolean(onUpdateDefaultRoles);
+
 	return (
 		<div className="flex flex-col gap-8">
 			{!isCustomRolesEnabled && (
@@ -55,6 +74,15 @@ export const CustomRolesPageView: FC<CustomRolesPageViewProps> = ({
 					documentationLink={docs("/admin/users/groups-roles")}
 				/>
 			)}
+			{showDefaultRoles && onUpdateDefaultRoles && (
+				<DefaultRolesSection
+					organization={organization}
+					availableOrgRoles={availableOrgRoles}
+					defaultRolesEntitled={Boolean(defaultRolesEntitled)}
+					isUpdatingDefaultRoles={Boolean(isUpdatingDefaultRoles)}
+					onUpdateDefaultRoles={onUpdateDefaultRoles}
+				/>
+			)}
 			<div className="flex flex-row gap-4 items-baseline justify-between">
 				<span>
 					<h2 className="mb-0 text-lg">Custom Roles</h2>
@@ -99,6 +127,100 @@ export const CustomRolesPageView: FC<CustomRolesPageViewProps> = ({
 	);
 };
 
+interface DefaultRolesSectionProps {
+	organization: Organization;
+	availableOrgRoles?: AssignableRoles[];
+	defaultRolesEntitled: boolean;
+	isUpdatingDefaultRoles: boolean;
+	onUpdateDefaultRoles: (roles: string[]) => Promise<void>;
+}
+
+const DefaultRolesSection: FC<DefaultRolesSectionProps> = ({
+	organization,
+	availableOrgRoles,
+	defaultRolesEntitled,
+	isUpdatingDefaultRoles,
+	onUpdateDefaultRoles,
+}) => {
+	const [isEditing, setIsEditing] = useState(false);
+
+	return (
+		<div className="flex flex-col gap-3">
+			<div className="flex flex-row gap-4 items-baseline justify-between">
+				<span>
+					<h2 className="mb-0 text-lg flex items-center gap-2">
+						Default Roles
+						{!defaultRolesEntitled && <PremiumBadge />}
+					</h2>
+					<span className="text-sm text-content-secondary leading-relaxed">
+						Roles attached to every member of this organization. An empty
+						selection limits new members to the floor permissions only.
+					</span>
+				</span>
+				<Button
+					type="button"
+					variant="outline"
+					onClick={() => setIsEditing(true)}
+					disabled={isUpdatingDefaultRoles || !defaultRolesEntitled}
+				>
+					Edit default roles
+				</Button>
+			</div>
+			<div className="text-sm">
+				{organization.default_org_member_roles.length === 0 ? (
+					<span className="text-content-secondary">
+						No default roles. New members receive only the floor.
+					</span>
+				) : (
+					<DefaultRolesSummary
+						roleNames={organization.default_org_member_roles}
+						availableRoles={availableOrgRoles}
+					/>
+				)}
+			</div>
+			{!defaultRolesEntitled && (
+				<p className="text-xs text-content-secondary mt-0 mb-0">
+					Editing organization settings requires a Premium license.
+				</p>
+			)}
+			<DefaultRolesDialog
+				open={isEditing}
+				currentRoles={organization.default_org_member_roles}
+				availableRoles={availableOrgRoles}
+				onCancel={() => setIsEditing(false)}
+				onConfirm={async (roles) => {
+					await onUpdateDefaultRoles(roles);
+					setIsEditing(false);
+				}}
+				isUpdating={isUpdatingDefaultRoles}
+			/>
+		</div>
+	);
+};
+
+interface DefaultRolesSummaryProps {
+	roleNames: readonly string[];
+	availableRoles?: AssignableRoles[];
+}
+
+const DefaultRolesSummary: FC<DefaultRolesSummaryProps> = ({
+	roleNames,
+	availableRoles,
+}) => {
+	const displayNameFor = (name: string): string => {
+		const role = availableRoles?.find((r) => r.name === name);
+		return role?.display_name || role?.name || name;
+	};
+
+	return (
+		<ul className="list-disc pl-5 m-0 flex flex-col gap-1">
+			{roleNames.map((name) => (
+				<li key={name}>{displayNameFor(name)}</li>
+			))}
+		</ul>
+	);
+};
+
 interface RoleTableProps {
 	roles: AssignableRoles[] | undefined;
 	isCustomRolesEnabled: boolean;
diff --git a/site/src/pages/OrganizationSettingsPage/CustomRolesPage/DefaultRolesDialog.tsx b/site/src/pages/OrganizationSettingsPage/CustomRolesPage/DefaultRolesDialog.tsx
new file mode 100644
index 0000000000000..86f89ba295596
--- /dev/null
+++ b/site/src/pages/OrganizationSettingsPage/CustomRolesPage/DefaultRolesDialog.tsx
@@ -0,0 +1,99 @@
+import type { FC } from "react";
+import { useState } from "react";
+import type { AssignableRoles } from "#/api/typesGenerated";
+import {
+	Dialog,
+	DialogActions,
+	DialogContent,
+	DialogDescription,
+	DialogFooter,
+	DialogHeader,
+	DialogTitle,
+} from "#/components/Dialog/Dialog";
+import { RoleSelector } from "#/modules/roles/RoleSelector";
+
+interface DefaultRolesDialogProps {
+	open: boolean;
+	currentRoles: readonly string[];
+	availableRoles?: AssignableRoles[];
+	onCancel: () => void;
+	onConfirm: (roles: string[]) => Promise<void>;
+	isUpdating: boolean;
+}
+
+export const DefaultRolesDialog: FC<DefaultRolesDialogProps> = ({
+	open,
+	currentRoles,
+	availableRoles,
+	onCancel,
+	onConfirm,
+	isUpdating,
+}) => {
+	if (!open) {
+		return null;
+	}
+
+	return (
+		<ActiveDefaultRolesDialog
+			currentRoles={currentRoles}
+			availableRoles={availableRoles ?? []}
+			onCancel={onCancel}
+			onConfirm={onConfirm}
+			isUpdating={isUpdating}
+		/>
+	);
+};
+
+interface ActiveProps {
+	currentRoles: readonly string[];
+	availableRoles: AssignableRoles[];
+	onCancel: () => void;
+	onConfirm: (roles: string[]) => Promise<void>;
+	isUpdating: boolean;
+}
+
+const ActiveDefaultRolesDialog: FC<ActiveProps> = ({
+	currentRoles,
+	availableRoles,
+	onCancel,
+	onConfirm,
+	isUpdating,
+}) => {
+	const [selected, setSelected] = useState<Set<string>>(
+		() => new Set(currentRoles),
+	);
+
+	return (
+		<Dialog
+			open
+			onOpenChange={(isOpen) => {
+				if (!isOpen) {
+					onCancel();
+				}
+			}}
+		>
+			<DialogContent>
+				<DialogHeader>
+					<DialogTitle>Edit default roles</DialogTitle>
+					<DialogDescription>
+						These roles are attached to every member of this organization. Use
+						an empty selection to grant new members only the floor.
+					</DialogDescription>
+				</DialogHeader>
+				<RoleSelector
+					hideLabel
+					availableRoles={availableRoles}
+					selectedRoles={selected}
+					onChange={setSelected}
+				/>
+				<DialogFooter>
+					<DialogActions
+						onCancel={onCancel}
+						onConfirm={() => onConfirm([...selected])}
+						confirmLoading={isUpdating}
+					/>
+				</DialogFooter>
+			</DialogContent>
+		</Dialog>
+	);
+};