Do "no requote" brokers still reject orders? How to test it

[FXS London Scalper]

Many brokers advertise no requotes. That doesn't mean every order gets filled at your price, and it's worth knowing what it does mean before choosing.

The mechanics: "no requote" almost always means market execution. The order fills at whatever price is available, so the requote is replaced by slippage. In fast markets you can also see rejections such as "off quotes" when there is no price to fill against.

How to test it cheaply:

• At two brokers, place the smallest allowed market orders in the first minute after a few high-impact releases such as US CPI and NFP.
• Record for each order: filled or not, requote or rejection, slippage in pips.
• Do the same at a quiet time as a baseline.

What to expect: the market-execution broker fills almost everything but with larger slippage in the first seconds, sometimes several pips, and the occasional rejection. An instant-execution broker requotes more but slips less on what it fills.

Neither is "better". Market execution is honest about fast markets; the cost just shows up in the fill. For scalping outside news, both are usually fine.

Has anyone tested this across several brokers? It would be useful to compare.

[Amanhasnoname]

I did a rough version of this with two brokers over about six release days, mostly CPI, NFP and one FOMC. The market-execution account filled every single order, but in the first fifteen seconds after the number the slippage ranged from nothing to a bit over three pips, and it was never in my favour on the big ones. The instant-execution account requoted me on almost half the orders in that same window, and on the fills I did get the slippage was tiny.

The quiet-time baseline was the useful part. Outside news both accounts were practically identical, with average slippage well under a tenth of a pip, so for normal scalping the label made no difference to my results at all.

What I took from it is that the choice only matters if you trade the release itself. I don't anymore, so I picked the account with the better commission and stopped worrying about requotes. If someone repeats this, I'd log the server timestamp of each fill too, because a delayed fill told me more than the price did.