At present, they are limited to outdoors settings, with no more than 10 people present.
Venues have been advised that their size will determine how many people can safely attend weddings and civil partnerships.
Baptism services will also be permitted under the latest changes.
It came as the latest figures from the Department of Health showed there have been no further coronavirus-related deaths in the North of Ireland over the weekend.
Its death toll still stands at 554.
The Executive said the date is dependent on the R-number, or reproduction number, remaining low and will be signed off by ministers at their meeting on Thursday.
The R-number is the average number of people that one coronavirus-infected person will pass the virus on to.
First Minister Arlene Foster said the sizes of weddings would be based on risk assessments carried out by individual venues that would allow couples and businesses to plan.
“I’m delighted we’re able to announce that they can now go ahead in a socially distanced way inside, no longer will they be limited in number,” she told a press conference on Monday.
It will be up to venues to decide their precise opening dates for wedding ceremonies and whether they want to provide facilities for wedding receptions.
The executive added that couples contacting registrars and officiants to rearrange their marriages should be aware that there is a backlog of couples waiting but every effort will be made to accommodate everyone as soon as possible.
The decision on indoor weddings and baptisms was taken by the executive at its meeting on Monday.
It is the latest move in the easing of the North of Ireland’s lockdown, as hairdressers, barbers and beauty salons resumed trading today.
On Friday, July 3, changes to the regulations allowed a range of sectors to reopen, including hotels, bars, restaurants, zoos, museums, galleries and bookmakers.