The country that you live in, check the brokers that are regulated by the government and have the broker license on them.
I have not calculated. But if you trade bond futures, you can get super high leverage based on bond notional amount.
If you have a large trading account why do you need high leverage? Brokers who offer high leverage will generally run B books, in other words they take the other side of your trades and they will do everything at their disposal to take your money. I have used ICMarkets and my experience was not good. You will find that if there is a market spike, the spike in their bars will be worse than the spikes seen with other brokers or that they will edit their bars after the spike event to make them look more reasonable. ( I have saved screenshots from the time of the event plus the next day) Ignoring all that, I trust their ASIC regulated company from the fund safety point of view but I wouldn't trust their offshore registered company Nor would I want to have all my trading funds with 1 broker. I would use at least 2 and preferably 3 or more brokers and I would use trade copying software to duplicate my trades in the new accounts. As an addition to IC Markets, may I suggest you try GlobalPrime and Pepperstone? GlobapPrime will not offer you very high leverage because they only do A books (they don't take the other side of your trades) 100:1 is their maximum but I managed to get 200:1 with them a couple of years ago and I still have it (although I don't need it). Pepperstone will offer higher leverage but they do B books like IC Markets . The spread and commissions are similar between all 3 brokers. You could probably get a commission free account with GlobalPrime plus reduced commissions if you ask Jeremy (tell him billV from the forum recommended them) so you will only get charged the spread (which is low). Pepperstone are less flexible but if you trade very high volume they will negotiate.
The real question is, how large will your Position values be? Available leverage is exactly for your situation. Are you going to hold 500M positions or only the 1M, if only 1M you can deposit just a fraction of that. Obviously you know this or you would not be attempting to trade such a large amount.
Very valid point and I should point out 1 risk which is not immediately obvious to all traders. The broker risk. We don't want to deposit all our funds with any 1 broker and we cannot trust brokers who register their business in unregulated jurisdictions. If we cannot eliminate this risk, at least we should reduce it by splitting our funds and depositing them with more than 1 broker. Its easy to duplicate our trades to more accounts, I use forex copier 3 but there are others out there.
Thank you very much! I indeed noted the spike differences in icmarkets but these did not affect my results yet. At least I am not aware of. I usually hold the positions for a a few hours and days, so the 1m spikes are more of an indicator to me. Will remember your advice when going to global prime!
The other advantage of duplicating trades with multiple brokers is better execution (because smaller size trades get filled quicker) and we can also compare the daily results between all the accounts so we can easily see if something is wrong.
It will take a bit of time to setup but its worth doing in my opinion because we want to protect our capital. I would set it up using demo accounts to make sure everything is ok. and when I'm happy with execution, lot sizes, SL etc I would then add the live accounts to it and delete the demos. Remember to save the Forex Copier 3 configuration with a couple of different names (main + backup) and to restart the PC to make sure the MT4 profiles are loading correctly and that the EA's (1 master + 1 or more slaves) are talking to each other. Forex copier 3 have good videos to watch so you can see how to set it up plus they have good support so you shouldn't have any problem.
I built over the years a great copy system which does much more than copying. It can earn me or refuse opening new trades if the margin or DD in the target is over a threshold, and it also monitors the market conditions to adjust the lot sizes being sent out of the source MT account, which basically runs several EAs. Also including a top-level web UI so I don't have to switch between different Mt5 accounts to check or adjust them.