diff --git a/app/routes/sequences.py b/app/routes/sequences.py
new file mode 100644
index 0000000..1f437a8
--- /dev/null
+++ b/app/routes/sequences.py
@@ -0,0 +1,85 @@
+"""Sequence routes — list, create, update (admin only)."""
+
+from __future__ import annotations
+
+import uuid
+
+from fastapi import APIRouter, Depends, HTTPException, status
+from sqlalchemy.ext.asyncio import AsyncSession
+
+from app.core.auth import check_permission
+from app.core.db import get_db
+from app.deps import get_current_user
+from app.schemas.sequence import SequenceCreate, SequenceUpdate
+from app.services import sequence_service
+
+router = APIRouter(prefix="/api/v1/sequences", tags=["sequences"])
+
+
+@router.get("")
+async def list_sequences(
+    db: AsyncSession = Depends(get_db),
+    current_user: dict = Depends(get_current_user),
+):
+    """List all sequences for the current tenant. Admin only."""
+    tenant_id = uuid.UUID(current_user["tenant_id"])
+    role = current_user.get("role", "viewer")
+
+    if not check_permission(role, "settings", "read"):
+        raise HTTPException(
+            status_code=status.HTTP_403_FORBIDDEN,
+            detail={"detail": "Insufficient permissions", "code": "forbidden"},
+        )
+
+    return await sequence_service.list_sequences(db, tenant_id)
+
+
+@router.post("", status_code=status.HTTP_201_CREATED)
+async def create_sequence(
+    body: SequenceCreate,
+    db: AsyncSession = Depends(get_db),
+    current_user: dict = Depends(get_current_user),
+):
+    """Create a new sequence. Admin only."""
+    tenant_id = uuid.UUID(current_user["tenant_id"])
+    user_id = uuid.UUID(current_user["user_id"])
+    role = current_user.get("role", "viewer")
+
+    if not check_permission(role, "settings", "create"):
+        raise HTTPException(
+            status_code=status.HTTP_403_FORBIDDEN,
+            detail={"detail": "Insufficient permissions", "code": "forbidden"},
+        )
+
+    data = body.model_dump()
+    return await sequence_service.create_sequence(db, tenant_id, user_id, data)
+
+
+@router.patch("/{sequence_id}")
+async def update_sequence(
+    sequence_id: str,
+    body: SequenceUpdate,
+    db: AsyncSession = Depends(get_db),
+    current_user: dict = Depends(get_current_user),
+):
+    """Update a sequence (name, prefix, padding only). Admin only."""
+    tenant_id = uuid.UUID(current_user["tenant_id"])
+    user_id = uuid.UUID(current_user["user_id"])
+    role = current_user.get("role", "viewer")
+
+    if not check_permission(role, "settings", "update"):
+        raise HTTPException(
+            status_code=status.HTTP_403_FORBIDDEN,
+            detail={"detail": "Insufficient permissions", "code": "forbidden"},
+        )
+
+    try:
+        sid = uuid.UUID(sequence_id)
+    except ValueError:
+        raise HTTPException(400, detail={"detail": "Invalid sequence_id", "code": "invalid_id"}) from None
+
+    data = body.model_dump(exclude_unset=True)
+    result = await sequence_service.update_sequence(db, tenant_id, user_id, sid, data)
+    if result is None:
+        raise HTTPException(404, detail={"detail": "Sequence not found", "code": "not_found"})
+    return result