AI API key vs subscription: two ways to connect your AI account

The first step in setting up any IFA Tools app is connecting the firm's own AI account, Claude from Anthropic or ChatGPT from OpenAI. There are two ways to do it: sign in with a subscription, or paste an API key. Both work. The choice between an AI API key vs subscription comes down to how the firm wants to be billed and how it wants to administer access, and it is worth making deliberately rather than by whoever happens to run the setup.

This article explains both routes in plain terms, the trade-offs, and the security habits that apply either way. We do not quote API prices, because they vary by provider and model and change over time; check the provider's own pages.

The two routes in IFA Tools setup

In the first step of the guided setup, called Your AI, the firm chooses Claude or ChatGPT. The app installs the AI tool it needs (Claude Code or Codex), then offers two ways to connect:

• Subscription. You sign in through the browser with the account for your Claude or ChatGPT plan.
• API key. You paste a key from the provider. The app checks it straight away and stores it in the computer's own keychain: macOS Keychain on a Mac, Windows Credential Manager on Windows.

Either way, the app then installs its skills for the AI, and from that point the AI work runs through the firm's own account. IFA Tools does not resell AI, does not sit between the firm and the provider, and does not hold the firm's client data. Documents are read on the computer and the content the AI needs is sent to the provider, under the firm's account. Settings lets the firm change any of this later.

How a subscription works

A subscription is a plan with the provider, paid at a set price per month or year, often per seat on business plans. The provider decides the usage allowance that comes with each plan.

For context, Anthropic's pricing page, seen on 7 October 2026 and priced in US dollars, listed Claude Pro at $20 monthly ($17 a month billed annually) and Team Standard at $25 per seat monthly ($20 billed annually). We have not confirmed ChatGPT plan prices, so check OpenAI's current pages. Prices may change.

What a subscription tends to suit:

• firms that already pay for a Claude or ChatGPT plan and want to use it;
• budgets that need a predictable monthly figure;
• people who would rather sign in than handle a credential.

The point to check is the allowance. If the plan's limits are reached in a busy month, work waits until the allowance resets or the plan changes. Compare your expected volume with the provider's published information for the plan.

How an API key works

An API key is a credential the provider issues so software can use its models directly. API use is generally billed according to how much is used, at the provider's published rates for each model, rather than at a flat plan price. Read the provider's current terms and pricing for the detail, including which terms govern API use, as they may differ from the terms for subscription plans.

What an API key tends to suit:

• firms that want AI cost to follow actual use, high in a review-heavy month and low in a quiet one;
• firms that want one central billing account for the firm rather than seats per person;
• firms with someone comfortable creating, recording and revoking credentials.

The point to check is spend. Usage billing is less predictable than a flat plan, so the firm should know where to see usage and whether the provider's account offers any limits or alerts.

AI API key vs subscription: the trade-offs side by side

Neither column is better in general. A two-adviser firm with existing plans and a firm that wants one central usage-billed account will reasonably make different choices.

Estimate your volume before you choose

Volume is what decides whether an allowance is comfortable or whether usage billing stays affordable. Our homepage uses these monthly volumes per adviser as a starting point (our estimates, not measurements of your firm):

• 5 annual reviews in Strata;
• 4 client documents in Carbon;
• 3 compliance files in Scrutineer;
• 6 meeting reviews in Asclto;
• 1 savings recommendation in Reckoner;
• 1 competency assessment in Freeboard.

Replace those with your own numbers, then run a representative batch during the first weeks and look at what it used. A full compliance file in Scrutineer, which reads every document in every subfolder, is a bigger job than a single meeting review, so weight your estimate towards the heavier tasks you run most. We cover honest before-and-after measurement in the cost of admin in a financial planning firm.

Security habits for either route

The route changes the credential, not the responsibility. The FCA's AI Update says, at paragraph 3.45, "Firms that use AI as part of their business operations remain responsible for ensuring compliance with our rules, including in relation to consumer protection." Treat AI access like any other system that touches client data:

• The firm owns the account. Use a firm account, not a personal one, so access and settings stay under the firm's control.
• Never share keys by email or chat. Paste a key directly into setup, where it is checked and stored in the keychain.
• Know which key is where. Keep a simple register of which computers or people use which key or seat, without recording the key itself.
• Revoke promptly. When someone leaves or a computer is replaced, remove the seat or revoke the key in the provider's account, and update the app in Settings.
• Check the training setting. Record the setting on your plan or API account. Anthropic's pricing page says its Team plan has "No model training on your content by default"; on consumer plans, training is opt-out.
• Keep the DPIA current. The provider processes client data either way, so it belongs in your DPIA whichever route you use.

For the broader reasons we use the firm's own AI account at all, see why IFA Tools runs on your own Claude or ChatGPT account.

Frequently asked questions

Is it safe to paste an API key into IFA Tools?

The key is checked straight away and stored in the computer's own keychain, macOS Keychain or Windows Credential Manager. IFA Tools does not sit between the firm and the AI provider. Keep the key out of email and documents, and revoke it in the provider's account if you think it has been exposed.

Can we start with a subscription and move to an API key later?

Yes. Settings lets the firm change any part of the setup later, including how the AI account is connected. Check the new route's terms and update your records when you switch.

Does IFA Tools charge for AI usage?

No. IFA Tools does not resell AI. The firm pays its AI provider directly, by subscription or API usage, in addition to the IFA Tools licence. Scrutineer, for example, is £99 per adviser per month excluding VAT.

To see the setup and a full file review running on a demo firm, look at Scrutineer or book a demo: twenty minutes on Microsoft Teams with Adam Booth, with nothing for you to prepare.