Claude Cowork vs ChatGPT Work: which one to use at work

If your work is mostly email, documents and spreadsheets, the agents that matter most to you right now are Claude Cowork and ChatGPT Work. You give them a whole job and they hand back the finished file for you to check. Claude Cowork vs ChatGPT Work? Here is what you need to decide, with the facts as of 24 September 2026.

What Claude Cowork and ChatGPT Work are

Claude Cowork is Anthropic’s agent for office work. It uses the same engine as Claude Code, but with nothing technical on show: you describe what you want and it hands back a document, an Excel file with working formulas or a tidy folder. Since 16 September 2026 Anthropic has been moving it into the normal Claude chat, starting with Pro and Max. Once that reaches you, the «Cowork» button disappears and you just ask in any conversation.

ChatGPT Work is OpenAI’s version. It came out on 9 July 2026, took the place of the old agent mode and has Codex technology inside. In ChatGPT you switch from Chat to Work with a selector.

Both ask permission before the important steps and can stay on a job for hours. If you need it every Monday, you leave it scheduled: scheduled tasks run in the cloud even with your computer off, except the ones that touch files on your computer, which need the computer on and the app open (that’s how it works on Claude and on ChatGPT). If you’re not sure yet what an agent is, start with what an AI agent is.

Is Claude Cowork free? Plans and prices in Spain

No: Cowork only comes with Claude’s paid plans. ChatGPT Work does have a free version, limited and only in the desktop app.

Monthly prices in Spain in September 2026. Both charge in euros. Anthropic shows its prices (in Spanish) before tax, so add VAT; OpenAI includes VAT on its personal plans, and on Business, if you enter your company’s tax ID at checkout, the purchase is VAT-exempt. Claude Pro drops to €15 a month if you pay for the year (€180 plus VAT). Team prices are per person on an annual plan, from two people. On Go, the €8 plan, Work is also limited and desktop only.

Neither is paid for separately: both draw on your plan’s usage limit. On Claude, the chat, Cowork and Claude Code share one allowance that renews every five hours, with a weekly cap. On ChatGPT, Work shares its limit with Codex. A long task uses far more than a question, and on Claude automatic mode uses more than manual.

Where they work: your computer, the cloud and your apps

This is where a lot of people get lost, and it’s exactly what affects your data.

Cowork works in Anthropic’s cloud, in an isolated environment for each session (in beta). If it needs nothing from your computer, it carries on when you close your laptop and you can check on it from your phone. To touch your files it needs the desktop app open, and it only goes into the folders you connect. Careful: whatever it opens from them is processed on Anthropic’s servers.

Work, on the web and on your phone, runs in OpenAI’s cloud and can’t see your disk: you upload files or it pulls from your apps. In the desktop app for Mac and Windows you can choose between working locally, with your files and programs, or in the cloud. Even locally, OpenAI warns that parts of your files and screenshots may travel to its servers.

With your apps they are very alike. Both connect to Gmail, Google Drive, Outlook, Teams, SharePoint and Slack, and both can drive a browser or even your computer (on Claude that last part is in beta and only on Pro and Max). With a business Microsoft 365 account, whoever manages your accounts will have to authorise the connection the first time, on ChatGPT for some actions. And Claude’s connector doesn’t accept personal accounts such as @outlook.com or @hotmail.com.

Both work in Spain.

Five tasks to test them yourself

Comparisons go stale in weeks, mine included. What helps is giving both the same task on a folder of fictional documents, and noting how long they take, how many times you have to correct them and whether they ask permission when they should.

1. PDF invoices into Excel

Invoices-test contains 40 fictional PDF invoices. Create invoices.xlsx with one row per invoice: source file, date, supplier, tax ID, net amount, VAT amount and document total. Check each amount against the PDF. Record multiple rates, withholding or other items separately; do not force a single formula. Mark absent data as “missing” and separate uncertain readings with a reason. Include counts and sums of known amounts. Do not change or move the PDFs.

What to look at: in this trial, compare all 40 invoices with their rows, review missing data and check the sum formulas. Checking five at random does not prove the remaining rows are correct.

2. A proposal from your scattered notes

Using the meeting notes I'm giving you, prepare a proposal for the client in Word, two pages at most: what we will do, deadlines, price and what is not included. Friendly but professional tone. If a detail is missing, don't make it up: leave it in square brackets.

What to look at: whether it invents anything (a price, a date) and how much you have to fix before sending it.

3. Tidying up a client’s folder

Look at the Client-test folder and propose how to organise it into subfolders by document type and year, and how to rename the files as YYYY-MM-DD-description. Show me the plan in a table and wait for my yes before moving anything. Don't delete any file.

What to look at: whether it really waits for your yes, and that the same files are there before and after.

4. A report on the competition

Search the internet for my five closest competitors, [your trade] in [your town]. Make me a table with name, website, services, prices if they publish them and Google rating, plus one page on what they do better than me. Add the link for each fact and keep facts separate from your opinions.

What to look at: open three links at random and check the fact is there.

5. Follow-ups from Gmail or Outlook

For this one, connect your email first.

Search my email for the quotes I sent in the last 30 days that the client hasn't answered. Give me a list with client, date and amount, and a short follow-up draft for each one. Don't send anything.

What to look at: whether it finds them all, whether it respects «don’t send anything» and whether the drafts sound like you. If the amount is in an attached PDF, Claude may miss it: its Gmail connector doesn’t read attachments.

When you finish, check how much of your limit each one used: on Claude in Settings, Usage; on ChatGPT in its usage dashboard.

Privacy: the settings to change before you hand over your files

Ten minutes on day one saves you most of the scares:

1. Check training and turn it off if enabled. In Claude it depends on your consent. On Claude: Settings, Privacy, the option to help improve its models. On ChatGPT: Settings, Data controls, «Improve the model for everyone».
2. No thumbs with client data. Rating an answer sends the whole conversation: Anthropic keeps it for up to five years and may use it for training.
3. Limited access and test data. Review ChatGPT permissions and safe use of Claude. Check what it can read, edit and send. Copies do not prevent leaks; start with fictional documents.
4. Connect only what you use, and have it ask before sending an email or sharing a file. Claude already works like that with Gmail and Google Drive.
5. With client data, check the account, agreement and permissions. Claude Team and ChatGPT Business don’t train on your data by default. With health data or anything as sensitive, ask whoever handles data protection first.

Claude Cowork vs Claude Code: when to step up

Cowork and Work are where to start, and the same plan also gives you Claude Code and Codex, which draw on the same limit. Claude Code mostly works in a folder on your computer and shows you every command it runs; Cowork runs its own in the cloud and gives you the result without the jargon. At OpenAI the difference is mostly presentation: according to the company, Work and Codex have the same core capabilities, and Codex shows the technical details that Work hides.

I’d step up when you want to build something of your own, like a quote calculator, automate a process or work through hundreds of files at once. I explain how to start in Claude Code and Codex for non-coders.

Claude Cowork vs ChatGPT Work: which one I would choose

• You already pay for ChatGPT Plus: use Work, you already have it.
• You already pay for Claude Pro: Cowork, no need to overthink it.
• You pay for nothing and want to try: ChatGPT Work in the desktop app, with the free account. You’ll run out of room quickly, but it’s enough to see how an agent works.
• You’ll pay for just one and your work is documents (proposals, contracts, reports): Claude Pro. To my taste it writes better and reviews more carefully.
• Your company lives in Microsoft 365: both connect to Outlook and Teams, and both have an Excel add-in. For that side, see the best AI for Excel.
• There are several of you and you handle client data: Claude Team or ChatGPT Business.

If one overtakes the other in a few weeks, I’ll tell you in the group.

Sources, checked on 26 September 2026: Claude prices (in Spanish), getting started with Claude Cowork, Cowork and chat in one Claude, Anthropic’s announcement of 16 September 2026, using Cowork safely, Claude’s Microsoft 365 connector, Claude Code cloud sessions, getting started with ChatGPT Work, ChatGPT Work and Codex pricing and limits, ChatGPT Work local security, ChatGPT release notes and ChatGPT Business billing.