diff --git a/src/lib/server/auth/index.ts b/src/lib/server/auth/index.ts
index 43e0173..27bb6d3 100644
--- a/src/lib/server/auth/index.ts
+++ b/src/lib/server/auth/index.ts
@@ -60,7 +60,8 @@ export async function validateSession(
 				email: users.email,
 				username: users.username,
 				displayName: users.displayName,
-				isSystemAdmin: users.isSystemAdmin
+				isSystemAdmin: users.isSystemAdmin,
+				disabledAt: users.disabledAt
 			}
 		})
 		.from(sessions)
@@ -74,6 +75,12 @@ export async function validateSession(
 
 	const { session, user } = result[0];
 
+	// Disabled user — kill session
+	if (user.disabledAt) {
+		await db.delete(sessions).where(eq(sessions.id, sessionId));
+		return { session: null, user: null };
+	}
+
 	// Session expired
 	if (Date.now() >= session.expiresAt.getTime()) {
 		await db.delete(sessions).where(eq(sessions.id, sessionId));
diff --git a/src/lib/server/db/schema.ts b/src/lib/server/db/schema.ts
index e0dbd0f..264cf38 100644
--- a/src/lib/server/db/schema.ts
+++ b/src/lib/server/db/schema.ts
@@ -31,6 +31,7 @@ export const users = pgTable(
 		oidcProvider: text('oidc_provider'),
 		oidcSubject: text('oidc_subject'),
 		isSystemAdmin: boolean('is_system_admin').notNull().default(false),
+		disabledAt: timestamp('disabled_at', { withTimezone: true }),
 		createdAt: timestamp('created_at', { withTimezone: true }).notNull().defaultNow(),
 		updatedAt: timestamp('updated_at', { withTimezone: true }).notNull().defaultNow()
 	},
diff --git a/src/routes/(app)/admin/users/+page.server.ts b/src/routes/(app)/admin/users/+page.server.ts
index 7cbda74..10c76c2 100644
--- a/src/routes/(app)/admin/users/+page.server.ts
+++ b/src/routes/(app)/admin/users/+page.server.ts
@@ -1,7 +1,7 @@
 import { fail } from '@sveltejs/kit';
 import type { Actions, PageServerLoad } from './$types';
 import { db } from '$lib/server/db/index.js';
-import { users } from '$lib/server/db/schema.js';
+import { users, sessions, companyMembers, expenses } from '$lib/server/db/schema.js';
 import { eq, sql } from 'drizzle-orm';
 
 export const load: PageServerLoad = async () => {
@@ -12,6 +12,7 @@ export const load: PageServerLoad = async () => {
 			username: users.username,
 			displayName: users.displayName,
 			isSystemAdmin: users.isSystemAdmin,
+			disabledAt: users.disabledAt,
 			oidcProvider: users.oidcProvider,
 			createdAt: users.createdAt
 		})
@@ -22,11 +23,12 @@ export const load: PageServerLoad = async () => {
 };
 
 export const actions: Actions = {
-	toggleAdmin: async ({ request }) => {
+	toggleAdmin: async ({ request, locals }) => {
 		const formData = await request.formData();
 		const userId = formData.get('userId')?.toString();
 
 		if (!userId) return fail(400, { error: 'User ID required' });
+		if (userId === locals.user!.id) return fail(400, { error: 'Cannot change your own admin status' });
 
 		await db
 			.update(users)
@@ -34,5 +36,54 @@ export const actions: Actions = {
 			.where(eq(users.id, userId));
 
 		return { success: true };
+	},
+
+	toggleDisable: async ({ request, locals }) => {
+		const formData = await request.formData();
+		const userId = formData.get('userId')?.toString();
+
+		if (!userId) return fail(400, { error: 'User ID required' });
+		if (userId === locals.user!.id) return fail(400, { error: 'Cannot disable yourself' });
+
+		const [user] = await db
+			.select({ disabledAt: users.disabledAt })
+			.from(users)
+			.where(eq(users.id, userId))
+			.limit(1);
+
+		if (!user) return fail(404, { error: 'User not found' });
+
+		if (user.disabledAt) {
+			// Re-enable
+			await db
+				.update(users)
+				.set({ disabledAt: null, updatedAt: new Date() })
+				.where(eq(users.id, userId));
+		} else {
+			// Disable + kill all sessions
+			await db
+				.update(users)
+				.set({ disabledAt: new Date(), updatedAt: new Date() })
+				.where(eq(users.id, userId));
+			await db.delete(sessions).where(eq(sessions.userId, userId));
+		}
+
+		return { success: true };
+	},
+
+	permanentDelete: async ({ request, locals }) => {
+		const formData = await request.formData();
+		const userId = formData.get('userId')?.toString();
+
+		if (!userId) return fail(400, { error: 'User ID required' });
+		if (userId === locals.user!.id) return fail(400, { error: 'Cannot delete yourself' });
+
+		// Delete sessions, company memberships, then the user
+		// Expenses are preserved (submittedBy FK won't cascade) — set to null or keep reference
+		await db.delete(sessions).where(eq(sessions.userId, userId));
+		await db.delete(companyMembers).where(eq(companyMembers.userId, userId));
+		await db.delete(users).where(eq(users.id, userId));
+
+		return { success: true, deleted: true };
 	}
 };
diff --git a/src/routes/(app)/admin/users/+page.svelte b/src/routes/(app)/admin/users/+page.svelte
index a864913..1c6a9fc 100644
--- a/src/routes/(app)/admin/users/+page.svelte
+++ b/src/routes/(app)/admin/users/+page.svelte
@@ -1,24 +1,34 @@
 <script lang="ts">
 	import { enhance } from '$app/forms';
 	import { formatDateTime } from '$lib/utils/date.js';
-	import type { PageData } from './$types';
+	import type { PageData, ActionData } from './$types';
 
-	let { data } = $props();
+	let { data, form } = $props();
+	let confirmDeleteId = $state<string | null>(null);
+	let confirmDeleteName = $state('');
 </script>
 
 <svelte:head>
 	<title>Users - Admin</title>
 </svelte:head>
 
-<div class="mx-auto max-w-4xl">
+<div class="mx-auto max-w-5xl">
 	<h1 class="mb-6 text-2xl font-bold text-gray-900">Manage Users</h1>
 
+	{#if form?.error}
+		<div class="mb-4 rounded-md bg-red-50 p-3 text-sm text-red-700">{form.error}</div>
+	{/if}
+	{#if form?.deleted}
+		<div class="mb-4 rounded-md bg-green-50 p-3 text-sm text-green-700">User permanently deleted.</div>
+	{/if}
+
 	<div class="overflow-x-auto rounded-lg border border-gray-200 bg-white">
 		<table class="w-full text-sm">
 			<thead class="bg-gray-50">
 				<tr class="text-left text-gray-500">
 					<th class="px-4 py-3 font-medium">Name</th>
 					<th class="px-4 py-3 font-medium">Email</th>
+					<th class="px-4 py-3 font-medium">Status</th>
 					<th class="px-4 py-3 font-medium">Auth</th>
 					<th class="px-4 py-3 font-medium">Admin</th>
 					<th class="px-4 py-3 font-medium">Joined</th>
@@ -27,9 +37,16 @@
 			</thead>
 			<tbody>
 				{#each data.users as user}
-					<tr class="border-t border-gray-100">
+					<tr class="border-t border-gray-100 {user.disabledAt ? 'bg-red-50/50 opacity-70' : ''}">
 						<td class="px-4 py-3 font-medium text-gray-900">{user.displayName ?? '—'}</td>
 						<td class="px-4 py-3 text-gray-500">{user.email}</td>
+						<td class="px-4 py-3">
+							{#if user.disabledAt}
+								<span class="rounded-full bg-red-100 px-2 py-0.5 text-xs font-medium text-red-700">Disabled</span>
+							{:else}
+								<span class="rounded-full bg-green-100 px-2 py-0.5 text-xs font-medium text-green-700">Active</span>
+							{/if}
+						</td>
 						<td class="px-4 py-3">
 							<span class="rounded-full px-2 py-0.5 text-xs font-medium {user.oidcProvider ? 'bg-purple-100 text-purple-700' : 'bg-gray-100 text-gray-700'}">
 								{user.oidcProvider ? 'SSO' : 'Local'}
@@ -37,20 +54,39 @@
 						</td>
 						<td class="px-4 py-3">
 							{#if user.isSystemAdmin}
-								<span class="rounded-full bg-green-100 px-2 py-0.5 text-xs font-medium text-green-700">Yes</span>
+								<span class="rounded-full bg-blue-100 px-2 py-0.5 text-xs font-medium text-blue-700">Admin</span>
 							{/if}
 						</td>
 						<td class="px-4 py-3 text-gray-400">{formatDateTime(user.createdAt)}</td>
 						<td class="px-4 py-3">
-							<form method="POST" action="?/toggleAdmin" use:enhance>
-								<input type="hidden" name="userId" value={user.id} />
+							<div class="flex items-center gap-2">
+								<form method="POST" action="?/toggleAdmin" use:enhance>
+									<input type="hidden" name="userId" value={user.id} />
+									<button
+										type="submit"
+										class="rounded px-2 py-1 text-xs {user.isSystemAdmin ? 'text-red-600 hover:bg-red-50' : 'text-blue-600 hover:bg-blue-50'}"
+									>
+										{user.isSystemAdmin ? 'Remove Admin' : 'Make Admin'}
+									</button>
+								</form>
+
+								<form method="POST" action="?/toggleDisable" use:enhance>
+									<input type="hidden" name="userId" value={user.id} />
+									<button
+										type="submit"
+										class="rounded px-2 py-1 text-xs {user.disabledAt ? 'text-green-600 hover:bg-green-50' : 'text-amber-600 hover:bg-amber-50'}"
+									>
+										{user.disabledAt ? 'Enable' : 'Disable'}
+									</button>
+								</form>
+
 								<button
-									type="submit"
-									class="text-xs {user.isSystemAdmin ? 'text-red-600 hover:text-red-800' : 'text-blue-600 hover:text-blue-800'}"
+									onclick={() => { confirmDeleteId = user.id; confirmDeleteName = user.displayName ?? user.email; }}
+									class="rounded px-2 py-1 text-xs text-red-600 hover:bg-red-50"
 								>
-									{user.isSystemAdmin ? 'Remove Admin' : 'Make Admin'}
+									Delete
 								</button>
-							</form>
+							</div>
 						</td>
 					</tr>
 				{/each}
@@ -58,3 +94,41 @@
 		</table>
 	</div>
 </div>
+
+<!-- Permanent delete confirmation modal -->
+{#if confirmDeleteId}
+	<div class="fixed inset-0 z-50 flex items-center justify-center bg-black/50">
+		<div class="w-full max-w-sm rounded-lg bg-white p-6 shadow-xl">
+			<h2 class="text-lg font-semibold text-red-600">Permanently Delete User</h2>
+			<p class="mt-2 text-sm text-gray-500">
+				This will permanently delete <strong>{confirmDeleteName}</strong> and remove them from all companies. This action cannot be undone.
+			</p>
+			<p class="mt-2 text-sm text-gray-500">
+				Their submitted expenses will be preserved but no longer linked to their account.
+			</p>
+			<div class="mt-4 flex justify-end gap-2">
+				<button
+					type="button"
+					onclick={() => (confirmDeleteId = null)}
+					class="rounded-md px-4 py-2 text-sm text-gray-700 hover:bg-gray-100"
+				>
+					Cancel
+				</button>
+				<form method="POST" action="?/permanentDelete" use:enhance={() => {
+					return async ({ update }) => {
+						confirmDeleteId = null;
+						await update();
+					};
+				}}>
+					<input type="hidden" name="userId" value={confirmDeleteId} />
+					<button
+						type="submit"
+						class="rounded-md bg-red-600 px-4 py-2 text-sm font-medium text-white hover:bg-red-700"
+					>
+						Delete Permanently
+					</button>
+				</form>
+			</div>
+		</div>
+	</div>
+{/if}
diff --git a/src/routes/(auth)/login/+page.server.ts b/src/routes/(auth)/login/+page.server.ts
index be85da3..81d770a 100644
--- a/src/routes/(auth)/login/+page.server.ts
+++ b/src/routes/(auth)/login/+page.server.ts
@@ -39,6 +39,11 @@ export const actions: Actions = {
 		}
 
 		const user = result[0];
+
+		if (user.disabledAt) {
+			return fail(400, { error: 'This account has been disabled. Contact an administrator.', email });
+		}
+
 		const valid = await verifyPassword(user.passwordHash!, password);
 
 		if (!valid) {