The EFL has issued a statement asking fans to arrive earlier than usual at games today following the terrorist incident in West London yesterday.
More than 20 people were injured on Friday morning as a bag containing explosive material went off on a District Line tube train at Parsons Green station.
As a result, the UK's terror threat level has been increased from severe to critical - its highest level - meaning that an imminent attack is likely.
The EFL statement read: "Following Friday's terror attack on the London Underground, the EFL – on police advice – is requesting that all supporters planning to attend EFL matches this weekend arrive at the stadium as early as possible.
"The rationale behind this request is to reduce numbers in crowded areas and will be applicable to all public events taking place this weekend.
"Supporters attending matches this weekend are reminded to be vigilant at all times and stay alert, not alarmed. If anyone does spot anything suspicious then they should contact a member of the home club's security staff or local police force immediately."
An 18-year-old man was arrested in Dover this morning in connection with the attack.