diff --git a/src/components/mika/PlansSection.tsx b/src/components/mika/PlansSection.tsx
index cedaa4c..8b152b9 100644
--- a/src/components/mika/PlansSection.tsx
+++ b/src/components/mika/PlansSection.tsx
@@ -1,8 +1,8 @@
 "use client";
 
 import { useState } from "react";
-import { Link } from "@tanstack/react-router";
-import { Check } from "lucide-react";
+import { Link, useNavigate } from "@tanstack/react-router";
+import { Check, Loader2 } from "lucide-react";
 import { useQuery } from "@tanstack/react-query";
 import { supabase } from "@/integrations/supabase/client";
 import { Button } from "@/components/ui/button";
@@ -18,6 +18,8 @@ import {
   DialogTrigger,
 } from "@/components/ui/dialog";
 import { EnterpriseLeadForm } from "./EnterpriseLeadForm";
+import { useAuth } from "@/hooks/use-auth";
+import { usePaddleCheckout } from "@/hooks/use-paddle-checkout";
 import { cn } from "@/lib/utils";
 
 interface PlanRow {
@@ -57,6 +59,26 @@ function usePlans() {
 export function PlansSection() {
   const [yearly, setYearly] = useState(false);
   const { data: plans, isLoading } = usePlans();
+  const { user } = useAuth();
+  const navigate = useNavigate();
+  const { openCheckout, loading: checkoutLoading } = usePaddleCheckout();
+  const [pendingSlug, setPendingSlug] = useState<string | null>(null);
+
+  const handleSubscribe = async (slug: string) => {
+    const cycle = yearly ? "yearly" : "monthly";
+    if (!user) {
+      navigate({ to: "/signup", search: { plan: slug, cycle } });
+      return;
+    }
+    const priceId = `${slug}_${cycle}`;
+    setPendingSlug(slug);
+    await openCheckout({
+      priceId,
+      userId: user.id,
+      customerEmail: user.email || undefined,
+    });
+    setPendingSlug(null);
+  };
 
   return (
     <section id="planos" className="py-20 sm:py-28 bg-background scroll-mt-20">
@@ -179,7 +201,8 @@ export function PlansSection() {
                         </Dialog>
                       ) : (
                         <Button
-                          asChild
+                          onClick={() => handleSubscribe(plan.slug)}
+                          disabled={checkoutLoading && pendingSlug === plan.slug}
                           className={cn(
                             "w-full rounded-lg transition-all duration-150 active:scale-[0.98]",
                             plan.highlighted
@@ -187,12 +210,14 @@ export function PlansSection() {
                               : "bg-foreground hover:bg-foreground/90 text-background",
                           )}
                         >
-                          <Link
-                            to="/signup"
-                            search={{ plan: plan.slug, cycle: yearly ? "yearly" : "monthly" }}
-                          >
-                            Assinar agora
-                          </Link>
+                          {checkoutLoading && pendingSlug === plan.slug ? (
+                            <>
+                              <Loader2 className="h-4 w-4 mr-2 animate-spin" />
+                              Abrindo checkout…
+                            </>
+                          ) : (
+                            "Assinar agora"
+                          )}
                         </Button>
                       )}
                       <p className="mt-3 text-xs text-muted-foreground text-center">
diff --git a/src/routes/painel.faturamento.tsx b/src/routes/painel.faturamento.tsx
index 331d81d..cd813f1 100644
--- a/src/routes/painel.faturamento.tsx
+++ b/src/routes/painel.faturamento.tsx
@@ -1,10 +1,12 @@
 "use client";
 
+import { useState } from "react";
 import { createFileRoute } from "@tanstack/react-router";
 import { format } from "date-fns";
 import { ptBR } from "date-fns/locale";
-import { CreditCard, ExternalLink } from "lucide-react";
-import { useSubscription, useProfile } from "@/hooks/use-profile";
+import { CreditCard, ExternalLink, Loader2 } from "lucide-react";
+import { toast } from "sonner";
+import { useSubscription } from "@/hooks/use-profile";
 import { useQuery } from "@tanstack/react-query";
 import { supabase } from "@/integrations/supabase/client";
 import { Button } from "@/components/ui/button";
@@ -16,7 +18,7 @@ export const Route = createFileRoute("/painel/faturamento")({
 
 function BillingPage() {
   const { data: subscription, isLoading } = useSubscription();
-  const { data: profile } = useProfile();
+  const [portalLoading, setPortalLoading] = useState(false);
 
   const { data: plan } = useQuery({
     queryKey: ["plan", subscription?.plan_id],
@@ -31,6 +33,20 @@ function BillingPage() {
     },
   });
 
+  const openPortal = async () => {
+    setPortalLoading(true);
+    try {
+      const { data, error } = await supabase.functions.invoke("create-portal-session");
+      if (error || !data?.url) {
+        toast.error("Não foi possível abrir o portal. Tente novamente.");
+        return;
+      }
+      window.open(data.url, "_blank", "noopener,noreferrer");
+    } finally {
+      setPortalLoading(false);
+    }
+  };
+
   return (
     <div className="space-y-8">
       <header>
@@ -75,10 +91,15 @@ function BillingPage() {
             </p>
           )}
           <Button
-            disabled={!profile?.stripe_customer_id}
+            disabled={!subscription?.paddle_subscription_id || portalLoading}
+            onClick={openPortal}
             className="mt-6 rounded-lg bg-primary hover:bg-primary-dark text-primary-foreground"
           >
-            <ExternalLink className="h-4 w-4 mr-2" />
+            {portalLoading ? (
+              <Loader2 className="h-4 w-4 mr-2 animate-spin" />
+            ) : (
+              <ExternalLink className="h-4 w-4 mr-2" />
+            )}
             Gerenciar assinatura
           </Button>
         </section>