Think https://www.tradingview.com/ might be live.
Worth an investigation.

Goto this site and click on fullfeatured chart
https://www.tradingview.com/symbols/CME_MINI-ES1!/

That's given me a much clearer view for what I need.

Thank-you to all who posted. It's really appreciated.

Q: upgraded to a paid plan but my data is delayed

Our paid plans don’t give you access to official real-time data from the exchanges unless this data is free by default (e.g. FX or Cryptocurrencies). Most of the stock exchanges that we support charge fees for the real-time data and we are unable to cover those costs even if you have a paid plan. TradingView doesn’t earn anything from these charges, however, per exchange regulations, we must collect these payments and remit them to the exchange and report users. Learn more about the supported markets & their prices.

You can purchase real-time data for any particular exchange at any given time from your User Profile page - > Account & Billing tab -> by clicking on the Add Real-Time Market button.

Sure.

First of all, CME rules require you to either have a funded broker account or to pay the professional fee (currently I believe it's $105 per month ) to access iive CME data, other than for a short (2-week) demo trial. Most brokers will extend the first 2 weeks another two on request, giving you a month, after which they want you to apply for and fund an account.

Yes, it's highway robbery, but it's their game and their rules. CME gets paid as a part of your per-transaction fee, and so they want you to access the data through a broker so you can be making live transactions.

I went to the helpful link provided above by @olobay, apparently provided by the AMP brokerage, and just clicked on the instructions for a Rithmic feed. Sure enough, you can get a 30 day demo of live data, but after that you need to open an account with AMP (or actually, any broker, but this was provided by AMP, after all.) You can't get around this, because it's CME rules.

Actually, you can. One way is to go to many different brokers and ask for their free demo every month. This would be tedious, and not exactly honest, and you would run out of places to go after a time (there are only so many data providers.). Also, if you really want to use ATAS, I don't know how many brokers will offer that. You would be using one of the platforms that the broker provides and is compatible with.

Or, it is possible to just pay the $105 professional fee for data every month, but you probably don't want to (every month is a lot worse than depositing the money once in an account and being able to get it back ). I don't think brokers are going to offer this (the fee goes to the exchange, so there's nothing for them). I have seen it offered by the Sierra Chart trading platform, but that leaves out your ATAS.

Or, you could just open an account with AMP or some other broker. I'm making no recommendations, but I notice that AMP only wants a hundred bucks as a minimum. I don't know if they open UK accounts, but I think they do. So, of course, do many others. And no one says you have to stay in one place forever.

Basically, your only realistic option, after perhaps a few free demo trials, is to have an account at a broker. Find one with a small minimum that opens UK accounts.

Bob.

FWIW, AMP is probably the least expensive game in town. In the US at least, if you don't need market depth for DOM trading, you can get level 1 top-of-book CQG data for indices and currencies for $1/month. The full CME top of book bundle is $3/mo. If you need level 2, then it's $10/mo or $30 for the full bundle.