Locations we like

Halls and Clubs Hart House, University of Toronto
The Great Hall and Courtyard are great for large weddings, and the Music Room is lovely. You can book the debates room for a wedding as well as the Gallery Grill. The historical non-denominational Chapel is pretty for smaller weddings (up to 35)
Multifaith Centre, UofT, College and Spadina. Various size rooms (ask me for details)
Arts and Letters Club
St Lawrence Market Kitchen
St Lawrence Market Hall
Royal Conservatory of Music
Ontario Heritage Centre (Adelaide)
Parks and Gardens and Beaches To reserve Toronto Park locations for ceremonies, see EVENTS. Note: Toronto limits large formal weddings to a few large locations such as Edwards Gardens, and will not issue a permit for most small parks, as they cannot manage issues around supervision and park damages due to weddings. High Park is no longer available as a venue due to abuse. Here is a discussion on parks and outdoor spaces. However, small parks, beach-fronts, even ravines (watch ticks!) may be used discreetly for small private elopements or micro-wedding the size of a small picnic (4-12 people). Read our post about small weddings and City Parks on ElopeToronto.
Hotels and inns Any Hotel will host a wedding, big or small. Some smaller boutique hotels do not have large rooms or public spaces, though you can rent a suite. The Gladstone and Royal York will hold family-size weddings as well as bigger events. We’ve used the Drake, and Park Hyatt, Four Seasons, etc. for intimate weddings: the palatial Hyatt suite will hold a large family wedding in the living room and has an enormous wet bar, the Four Seasons will rent you a large suite with kitchen and private chef. The King Edward has period rooms suitable for private elopements and small family weddings. You can also book the mezzanine terrace with chairs for 40-50. Boutique hotels are fun, such as the Templar, Le Germain. The Windsor Arms is nice for hotel elopements, and the Tea Room is possible for a small elegant wedding. Almost any Bed and Breakfast (charming ones) could host a simple wedding, or you could rent an apartment with a view. Try your friends party rooms at a swanky condo, too.
Historic Locations
and Museums
You may book some of Toronto’s Historic Museums . Many historic sites have outdoor gardens for good weather, and indoor facilities as well. We like Todmorden Mills (I was the volunteer historic gardener at the Mills, and have married several couples here, ask me). Most weddings are in the Mill Gallery. Try Spadina House – usually on the steps.  Try the Enoch Turner Schoolhouse, (airy hall or schoolroom). Consider other interesting city locations, like the the Brickworks or Wychwood barns. We have married people splendiferously at the ROM, the AGO and the Royal Conservatory of Music, but also in contemporary museums, like the Gardiner Museum . You can ask almost any art gallery for rental procedures for events when they are dark. Some do not advertise weddings, so just enquire whether they will host a private event. (Don’t use the word ‘wedding’ until you find out if they are open to private rental). We’ve also used storefronts, closed for the evening, theatres, storefront galleries, even the VIP room at the Paramount Theatre Cineplex, and the Art Deco Fox Cinema in the beaches. Yes, you can rent the conservatory at Casa Loma for an elopement. It’s the same fee for 4 people as for 150.
Small and Medium sized Restaurants as venues When contacting restaurants, ask for a half-hour slot in a semi-empty restaurant ‘between service’;  11am for lunch, or 4:00 for dinner, and then stay and eat there. We did a small wedding at  AGO bistro before dinner. Also book the Grange Library with splendid Afternoon Tea.  Be sure to emphasize you are having a simple function, a civil ceremony, no fuss; no chair wrapping, no confetti or other cleanup problems, and a restaurant may be happy to serve the champagne and accommodate you. We also hold weddings at performance spaces and clubs, such as the Richmond the Design Exchange, even TIFF.  Highly recommend the Gallery Grill at Hart House for smaller (30-50?) weddings. The food couldn’t be better, and the space is great.
or charming
Market Kitchen Mezzanine at St. Lawrence Market. Consider a library meeting room, or rent a smaller non-religious meeting room at a local church. Some are quite pretty, nice wood and stained glass, and often cheap. St George the Martyr Anglican Church, behind OCAD & AGO, offered the Garden and/or the Sanctuary for small to medium non- denominational weddings or receptions. This is also the home of the Music Gallery, and a concert venue.
Unusual sites Micro-weddings and pop-ups Although Micro-weddings and Popup weddings are fun for a small handful of people, we do NOT recommend or accept Flashmob weddings. Taking over public spaces for a wedding is inconsiderate. And we need sufficient calm for the actual wedding ceremony. Even the ‘wedding’ on the float on the Pride Parade was a re-enactment, as we held the real wedding at the Windsor Arms the night before. Though, once you’ve held the legal wedding, you can have fun with pictures.  I was once asked to marry a couple while skydiving north of Toronto, but weather intervened. Wind is also a problem with Hot Air balloons, so we had to postpone a Fall ‘aloftment’ in Newmarket. Mary HAS flown a small plane, tho! We have used the Skypod at the CN Tower and the rink at Nathan Phillips Square, and two librarians booked me (a third librarian) into the secret stacks at a library. I finally held a wedding on a (rented) streetcar! Note that you can be MARRIED on a boat, in a plane, on the Mariposa tour boat or in a canoe, but you still have to sign the documents on land.  You can read about ‘boats, planes, trains and aeroplanes’ – HERE.