Is spread taken into account in expert advisors?

 
Hey!
I have set up an EA that buys at ASK price. I want to know if it takes (in backtesting) into account spread history and opens trades according to it or should I manually add to my TP to simulate real market?
 
  1. Aymane Maizi: I have set up an EA that buys at ASK price.

    That is the only place you can buy.

  2. Aymane Maizi: should I manually add to my TP to simulate real market?

    You buy at the Ask and sell at the Bid. Pending Buy Stop orders become market orders when hit by the Ask.

    1. Your buy order's TP/SL (or Sell Stop's/Sell Limit's entry) are triggered when the Bid / OrderClosePrice reaches it. Using Ask±n, makes your SL shorter and your TP longer, by the spread. Don't you want the specified amount used in either direction?

    2. Your sell order's TP/SL (or Buy Stop's/Buy Limit's entry) will be triggered when the Ask / OrderClosePrice reaches it. To trigger close to a specific Bid price, add the average spread.
                MODE_SPREAD (Paul) - MQL4 programming forum - Page 3 #25

    3. The charts show Bid prices only. Turn on the Ask line to see how big the spread is (Tools → Options (control+O) → charts → Show ask line.)

      Most brokers with variable spreads widen considerably at end of day (5 PM ET) ± 30 minutes.
      My GBPJPY shows average spread = 26 points, average maximum spread = 134.
      My EURCHF shows average spread = 18 points, average maximum spread = 106.
      (your broker will be similar).
                Is it reasonable to have such a huge spreads (20 pip spreads) in EURCHF? - General - MQL5 programming forum (2022)

 
William Roeder #:
  1. That is the only place you can buy.

  2. You buy at the Ask and sell at the Bid. Pending Buy Stop orders become market orders when hit by the Ask.

    1. Your buy order's TP/SL (or Sell Stop's/Sell Limit's entry) are triggered when the Bid / OrderClosePrice reaches it. Using Ask±n, makes your SL shorter and your TP longer, by the spread. Don't you want the specified amount used in either direction?

    2. Your sell order's TP/SL (or Buy Stop's/Buy Limit's entry) will be triggered when the Ask / OrderClosePrice reaches it. To trigger close to a specific Bid price, add the average spread.
                MODE_SPREAD (Paul) - MQL4 programming forum - Page 3 #25

    3. The charts show Bid prices only. Turn on the Ask line to see how big the spread is (Tools → Options (control+O) → charts → Show ask line.)

      Most brokers with variable spreads widen considerably at end of day (5 PM ET) ± 30 minutes.
      My GBPJPY shows average spread = 26 points, average maximum spread = 134.
      My EURCHF shows average spread = 18 points, average maximum spread = 106.
      (your broker will be similar).
                Is it reasonable to have such a huge spreads (20 pip spreads) in EURCHF? - General - MQL5 programming forum (2022)

Thank you William. I understand now.

 
Aymane Maizi:
Hey!
I have set up an EA that buys at ASK price. I want to know if it takes (in backtesting) into account spread history and opens trades according to it or should I manually add to my TP to simulate real market?
Just wanted to point out that there is actually a setting option in strategy tester to set the spread if you want to. There is never a need to add it to your TP. And also you'll need to key in commission manually if you're using metaquote for back testing. 
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