# Pa · Payments — element 34 of 58

> The revenue element. Turns product into income.

- **Group:** 7 · Sales & Revenue
- **Necessity:** Essential
- **Price band:** $ · under $30/mo
- **Maturity:** Stable
- **Edition:** v2026.Q3 · verified 2026-09-13

## Leading tools (v2026.Q3)

- **Stripe** — the revenue default
- **Polar** — mor for ai devs
- **Paddle** — the proven mor
- **Orb** — usage billing, enterprise grade
- **Lago** — open-source billing engine

## Our take

Stripe plus usage-based billing covers the 2026 pricing playbook. Set it up before you think you need it.

## Combines with

In, Ac, An


## The top 5 — deep dossier (verified 2026-09-13)

Stripe, and it isn't close — $1.9T processed in 2025 (1.6% of global GDP), native usage meters, the Metronome acquisition folding the OpenAI/Anthropic billing layer into the platform, and the Agentic Commerce Protocol co-authored with OpenAI making it the default rail for selling to both humans and agents. Polar is the pick when you're a small team selling AI software globally and want a merchant of record with LLM-token billing out of the box; Paddle when you're a proven SaaS or app business that wants the veteran MoR with humans behind it; Orb (now Adyen) when usage-and-credits pricing is the product and you're past Series A; Lago when you refuse to rent your billing stack.

1. **Stripe** (Stripe, Inc.) — Cards 2.9% + 30¢ (+1.5% intl) · Billing 0.7% PAYG or from $620/mo · Managed Payments MoR +3.5% · Metronome startup tier w/ $100K allotment · agentic Shared Payment Tokens $0.15 each. Best for: The default revenue stack for an AI-era startup — checkout, subscriptions, usage meters, tax, and agent-facing commerce on one API you'll never fully outgrow. Why: Businesses on Stripe generated $1.9T in 2025 (+34%, 1.6% of global GDP) and its Revenue suite is tracking toward a $1B run-rate. It bought Metronome (Dec 3, 2025) — the layer that bills OpenAI, Anthropic, and NVIDIA — and co-authored the Agentic Commerce Protocol with OpenAI, powering ChatGPT Instant Checkout. Every upgrade path (MoR via Managed Payments, usage billing via Metronome, machine payments via x402/MPP) now lives in-house. Watch: Fees stack: Billing + Tax + Radar + Managed Payments can push all-in cost past a flat-fee MoR. Not a merchant of record by default — you carry global tax liability unless you pay the +3.5% Managed Payments adder. Complexity is real; small teams routinely underestimate the integration surface. [https://stripe.com](https://stripe.com)
2. **Polar** (Polar Software (open source, Apache-2.0)) — Starter free, 5% + 50¢ · Pro $20/mo, 3.8% + 40¢ · Growth $100/mo, 3.6% + 35¢ · Scale $400/mo, 3.4% + 30¢ · startup program: 12 mo free at Scale rates. Best for: Solo devs and small AI teams who want a merchant of record — sales tax, VAT, chargebacks handled — plus usage, credits, and LLM-token billing without building any of it. Why: The MoR built specifically for AI-era software: meter tokens, API calls, and GPU time down to the event, with LLM billing wired into the Vercel AI SDK. Open source (Apache-2.0, ~9.9k GitHub stars) with a $10M Accel-led seed (Jun 2025) and users like Tailwind CSS, FastAPI, and Midday. It compresses Stripe + tax + entitlements + metering into one checkout. Watch: A seed-stage company sitting in your entire revenue path — counterparty risk is the honest price. Fees run 1–2 points above raw Stripe, and the May 2026 'Polar Plans' repricing added monthly platform fees where a flat 4% + 40¢ used to be. [https://polar.sh](https://polar.sh)
3. **Paddle** (Paddle.com Market Ltd) — 5% + 50¢ per checkout (all-in: MoR, global tax, fraud, support) · custom rates at scale · sub-$10 products and invoicing need a quote. Best for: SaaS and app businesses past first revenue that want the proven merchant of record — one vendor eating tax, compliance, chargebacks, and support across 200+ markets. Why: The scaled MoR: 10,000+ businesses, $130M in sales taxes remitted last year, customers from Fortinet to Tailwind Labs and n8n. It won the vibe-coding wave's distribution prize — 'Lovable Payments, powered by Paddle' makes it the default checkout for prompt-built apps — and its App2Web push targets the Apple-tax arbitrage every consumer AI app now runs. Watch: 5% + 50¢ is the priciest headline rate in this table, and onboarding involves real vetting — approval isn't instant. It's a packaged platform, not a primitives API: deep custom billing logic fits Stripe or a billing layer better. [https://www.paddle.com](https://www.paddle.com)
4. **Orb** (Orb → Adyen (closed Jul 1, 2026)) — Custom (Core / Advanced / Enterprise), priced on invoice billings + events ingested — no public rate card. Best for: Series A+ companies whose pricing IS the product — usage, credits, prepaid thresholds, hybrid seats — and who keep their own payment processor. Why: The reference usage-billing platform for AI infrastructure: Vercel, Replit, Supabase, Fal, and Writer run on it, it's stress-tested past 250,000 events/second, and it shipped agentic payment-method support (shared payment tokens) before any rival. The Adyen acquisition (closed Jul 1, 2026) puts a payments giant behind it while Orb pledges standalone operation and processor neutrality. Watch: No public pricing — expect a sales cycle and real invoices. Acquisition integration risk is unproven despite the neutrality pledge; the Metronome-into-Stripe precedent shows independents get pulled toward their owner's rails. Overkill below ~$1M ARR. [https://www.withorb.com](https://www.withorb.com)
5. **Lago** (Lago (open source, AGPL-3.0 core)) — Open-source self-host free (AGPL-3.0) · Lago Premium (cloud or self-hosted) custom, with paid add-ons for premium ingestion, tax, 24/7 support. Best for: Teams that must own the billing stack — self-hosting, EU data residency, gateway neutrality, or pricing logic too weird to rent. Why: The open-source billing engine AI's fastest companies actually run: Mistral AI, Groq, Gladia, Synthesia, and Laravel are customers. AGPL core with 9.7k stars and steady releases (v1.46, May 2026), metering-to-invoice in one self-hostable stack, and payment-gateway orchestration across providers — the only top-5 path with zero platform lock-in. Watch: The gap between the free core and Premium is wide, and Premium pricing is opaque contact-us territory. Self-hosting billing is genuine ops burden — dunning, tax, and invoice edge cases become your on-call problem. [https://www.getlago.com](https://www.getlago.com)

### How to choose
- If You're pre-revenue or unsure what your pricing will be → Stripe. 2.9% + 30¢, usage meters included, and every future need — MoR, Metronome-grade usage billing, agentic checkout — is an upgrade, not a replatform. One in five Atlas startups now charges within 30 days of incorporating; be one.
- If You're a small team selling AI software globally and refuse to touch VAT registrations → Polar — the 1–2 point MoR premium is cheaper than compliance, and LLM-token billing comes free. Creem or Dodo if you want a flat-fee indie alternative.
- If You're past ~$1M ARR with a subscription product and want one vendor liable for tax, fraud, and chargebacks everywhere → Paddle — 10,000+ businesses and $130M in tax remitted last year say the model works; or Stripe Managed Payments (+3.5%) if you're already deep on Stripe.
- If Usage, credits, or outcome pricing IS your product (AI infra, agents, GPU time) → Orb if you're enterprise-track, Metronome-inside-Stripe if you're all-in on Stripe rails, Lago if you must self-host. Prepaid credits with threshold billing are the 2026 default for controlling fraud and runaway spend.
- If You want agents to buy from you — or your agent to buy things → Implement ACP product feeds + Stripe Shared Payment Tokens today (that's the only rail live in ChatGPT), support x402 for machine-to-machine API payments, and watch AP2 — but don't bet the stack on any protocol yet; even Stripe puts the industry at level 1–2 of 5.

### The field (20 more)

Metronome (acquired), Lemon Squeezy (acquired), m3ter (acquired), OpenMeter (acquired), Creem, Dodo Payments, Autumn, Paid, Schematic, Chargebee, Zuora, FastSpring, Gumroad, RevenueCat, PayPal / Braintree, Adyen, Skyfire, x402, AP2 (Agent Payments Protocol), ACP (Agentic Commerce Protocol)

Full dossier data: https://elems.ai/e/pa.json

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Source: [elems.ai](https://elems.ai/e/pa.html) — the periodic table of the AI-led startup. Data: https://elems.ai/elements.json (CC BY 4.0, cite elems.ai).