The new entrance is designed to provide “a significantly safer and more secure environment for screening while also protecting the 400,000 visitors, 1,000 daily pass-holders and the infrastructure of the Parliament building”.
The public can enter the parliament through the new entrance today and leave through the existing exit while work on a new exit continues.
The project remains on time and on budget for a total cost of £6,488,800, according to Holyrood Presiding Officer Tricia Marwick.
She said: “The SPCB (Scottish Parliamentary Corporate Body) took the decision to build an external security facility on the basis of clear and consistent security advice.
“I am pleased to report that it will open on time and the project remains on budget.
“We have enhanced the security of the building, but have achieved it in such a way that the Parliament will continue to feel open and accessible to the people of Scotland.”
The new entrance offers more space for screening, a baggage drop and enhanced accessibility features such as an induction loop.
Work on the new exit is scheduled to conclude in September, with the old exit door due to be closed off shortly thereafter.
Throughout this final period of work, the building will remain open to the public, with the public cafe and visitor tours operating as usual.