For instance the hotel gives the OTA a rate of €80, and the OTA marks it up with €20, to sell at €100. In this case the mark-up % is 25%.
So the formula of Markup is:
Markup = Selling Price - Net Room Rate
Markup % = Markup / Net Room Rate
A common mistake made in the hotel industry is to confuse markup with margin. This is because OTA working with a net rate model also use a commission in the contract or distribution agreement with hotels. If we take the example above with a markup of €20 and a final sell rate of €100, the margin in this case would be 20% (while the markup is 25%).
Here some more formulas to put this in perspective:
It is just math ,-) , and simply depends where you start your calculation ... at the sell rate or the net rate.