How much can you use an AI assistant before you hit a limit? Usage limits on paid ChatGPT, Claude, Copilot and Gemini plans

No vendor publishes a figure for a full working day. On 1 October 2026 only OpenAI gave message numbers for a business seat, and those were ranges: an estimated 5 to 2,000 messages per five-hour window in its Work and Codex tools, depending on the model, plus 15 Pro-model messages a month. Anthropic, Microsoft and Google gave multipliers, feature counts or nothing.

For a firm that wants an assistant open from nine to five, the limit decides whether one seat a person is enough. Below is what each vendor's own help pages said on the day. We read the pages and tested nothing.

The four at a glance

ChatGPT

OpenAI's help page for ChatGPT Business gives the most detail of the four. Ordinary chat on the fastest setting, Instant, is described as virtually unlimited, subject to safeguards against misuse. The page says this does not make reasoning, Pro models, ChatGPT Work, Codex or other tools unlimited, and it gives no number for the reasoning allowance.

For the Pro models, a standard seat includes 15 messages a month and a premium seat 50 a week. For Work and Codex, the tools that carry out longer tasks, the page gives estimates for a standard seat per five-hour window. They run from 5 to 45 messages on GPT-6 Astra to 250 to 2,000 on GPT-5.6 Luna. OpenAI adds that a long task uses more of the allowance than a short one, so a message count is not a reliable guide to what is left. A premium seat has five times the usage and no five-hour limit. The UK pricing page showed a standard seat at £15 a month and a premium seat at £75, both billed annually, so five times the usage costs five times the price.

At a limit, usage can continue on credits the workspace has bought, if its spending controls allow. Otherwise the user waits for the reset; OpenAI's support team does not reset limits.

For ChatGPT Plus, the plan for individuals, the pages we read gave no number; at a reasoning limit ChatGPT may continue with another model.

Claude

Anthropic gives no message numbers at all. Its pricing page says usage depends on the length of the conversation, the model and the features used, "so there's no fixed message count".

It gives a structure and multipliers instead:

• Every paid plan has a session limit that resets every five hours and a weekly limit across all models.
• A Team standard seat has 1.25 times the Pro plan's allowance per session. A Team premium seat has 6.25 times. The Max plans for individuals have 5 or 20 times.
• Limits on a Team plan belong to each member and are not shared.
• Chat, the desktop app and Claude Code all draw on the same allowance, and Anthropic says it may limit usage in other ways to manage capacity.

At a limit the member waits, moves to a premium seat, or uses credits if the owner has turned them on. Credits are bought in advance on a Team plan and billed at Anthropic's standard API rates, and the owner can set a monthly spending limit for the firm and for each person.

The UK version of Anthropic's pricing page showed a standard seat at £18 a month and a premium seat at £90, billed annually and including 20% VAT: five times the price for five times the session allowance, the same ratio as ChatGPT.

Copilot

Microsoft publishes no usage figure for the paid Microsoft 365 Copilot licence. Its overview page, updated on 10 September 2026, describes the licence as "priority access" to Copilot's capabilities and to its reasoning models.

The same page describes the free Copilot Chat that comes with eligible Microsoft 365 plans as standard access, subject to service capacity: if the service is not available at a given moment, Copilot tells the user and does not interrupt a task already running.

What the licence costs is in our Microsoft 365 Copilot cost guide.

Gemini

Google publishes a table of limits for the AI features inside Workspace, updated on 1 October 2026. For Business Standard and Business Plus it includes:

• 5,000 uses a month of the AI function in Sheets
• 100 generated slides a month in Slides
• 100 a month for building and editing spreadsheets
• 20 audio overviews of PDFs a day

Business Starter has no access to those four. An add-on called AI Expanded Access raises them to 25,000, 500, 500 and 40. Limits are for each user and are not pooled. Daily limits reset at midnight Pacific Time, monthly limits on the first of the month, and unused allowance does not roll over.

For the Gemini app itself, the chat window, the Workspace table says only "Varies by feature". Google's help page for personal accounts says the app's limit is based on computing use, refreshes every five hours until a weekly limit is reached, and is two or four times the standard level on its AI Plus and AI Pro plans. It gives no message number either.

What this means for an office day

1. Plan around the five-hour window. ChatGPT and Claude use one, as does Gemini on personal accounts. If a window began at 9:00 and the allowance ran out at 11:00, it is back at 14:00.
2. Watch the weekly limit. Claude, and Gemini on personal accounts, add one on top, and a heavy week can stop a person until their reset day.
3. Know what uses the allowance. Anthropic's help pages name long conversations, large attachments, web search, connected tools, model choice and multi-step tasks. An assistant that works through files and tools will use more than one that answers short questions.
4. Decide the overflow in advance: a larger seat for the heaviest users, or credits with a monthly spending limit. OpenAI and Anthropic both let the owner set one.
5. Trial it for two weeks with the heaviest users before buying seats for everyone.

The tax treatment of the subscription is in our guide to claiming an AI tool as a business expense. For what the business plans cost a small firm, see our guides for restaurants and pubs and online shops.

Overlyft is an AI agency that sets up AI office assistants for ten trades: they are set up in the firm's own office for a fixed price agreed after an audit, the firm pays Anthropic directly for its own Claude plan, and a person approves anything that goes to a customer.

Limits change often. Check each vendor's help page on the day you buy.