Flats are back: ballet flats, Mary Janes and slingbacks, properly

The flat shoe has had its best year in a generation. Google's summer report on Canadian searches put ballet flats and Mary Janes at all-time highs and flagged slingback flats as a breakout, and the evidence is on every streetcar: the ballet flat with the ribbon tie, the Mary Jane with the strap and the sensible heel height of zero, the slingback that bares the heel and somehow makes a flat look dressed. After a few years of chunky soles and a few more of impossible heels, the city has decided it would like to walk again.

A flat is the most honest shoe there is. There is no heel to hide a poor last, no platform to forgive a bad sole, and no excuse: it either fits and holds up or it does not. Which makes it worth buying carefully, and in person.

The three shapes, and who they suit

The ballet flat is the soft one: a low vamp that shows the top of the foot, a rounded or almond toe, a sole that flexes, and in the current versions a square toe and a ribbon or strap. It suits a narrow to medium foot and a low instep, and it is the most elegant of the three under a trouser that breaks at the ankle. Its weakness is the sole, which on the cheap versions is a sheet of cardboard that will not survive a Toronto spring; look for a real leather or rubber sole with some thickness, and expect to resole the good ones.

The Mary Jane is the structured one: a closed toe, a strap across the instep, a little lift at the heel or none at all, and a shape that reads as either schoolgirl or Parisian depending entirely on the leather. It suits a wider foot and a higher instep better than the ballet flat does, because the strap holds the foot rather than the vamp. It is the flat to wear with socks in October, with a midi skirt in May, and with tailored trousers at any time.

The slingback flat is the dressed one: a pointed or almond toe, a strap behind the heel, nothing at the back. It suits a narrow heel, and it is unforgiving on a wide one because the strap is what keeps the shoe on. It is the flat for dinner, for a wedding on grass, and for the office in the two months a year when bare heels are reasonable. It is not the flat for a February sidewalk, and it does not pretend to be.

The four checks before you buy

• Bend it. Hold the shoe at heel and toe and flex it at the ball of the foot. A flat that bends easily there and nowhere else will walk well; one that folds in the middle of the arch will hurt by lunchtime.
• Look at the sole from the side. A sliver of leather with no substance is a slipper. Look for a sole you can see, ideally with a rubber forepart or a full rubber sole for the city, and a heel piece you could replace.
• Check the heel counter. Pinch the back of the shoe above the heel. It should be firm and hold its shape; if it collapses, the shoe will slip and the back will break down within a season.
• Walk on a hard floor, late in the day. Feet swell by afternoon, and a flat that is snug at 10 a.m. is tight at 6 p.m. Leather gives a little at the width and not at all at the length, so the toe must be right from the start.

What to wear them with

The flat is a proportion tool, and its rule is simple: show the ankle or show the shape. A trouser that stops just above the ankle bone, a straight jean cuffed once, a midi skirt that ends at the slimmest part of the calf, a dress with a hem above the knee. Wide, floor-length trousers swallow a flat; a flare wants a heel. With a long coat, a flat looks considered rather than underdressed, which is why it has become the Toronto autumn uniform.

Socks are allowed again and, with the Mary Jane, encouraged: a fine ribbed sock in a colour that speaks to the shoe turns it into an outfit in October and keeps the shoe wearable into November. With a ballet flat, a sheer sock is the current move; with a slingback, no sock, and no arguing.

Buying them in Toronto

The flat is a shoe to try on, and the strongest selections in the city are with the boutiques that buy footwear seriously: the multi-brand stores of Yorkville for the European makers, and the independent shoe shops of Queen West for the mid-priced, the Canadian and the interesting. Browse women's flats in Toronto to see the current run, and read the Queen West guide and the Yorkville guide for where to walk in. If the flat is not quite enough shoe for the day, the kitten heel guide covers the next four centimetres.

Common questions

Are ballet flats bad for your feet?

A flimsy ballet flat with a thin sole and no support is hard on the foot over a long day, because the foot does all the work the shoe is not doing. A well-made flat with a real sole, a firm heel counter and a little cushioning is fine for most people, and better than a heel for a walking city. If you have flat arches, the Mary Jane's strap and a slightly thicker sole will serve you better than the softest ballet flat.

What is the difference between a ballet flat and a Mary Jane?

A ballet flat has a low, open vamp with no fastening, and relies on the shape of the shoe to stay on; a Mary Jane has a closed toe and a strap across the instep that holds the foot. The Mary Jane fits a wider range of feet and wears better with socks; the ballet flat is the softer, more delicate line.

Can you wear flats to a wedding?

Yes, and for a garden or daytime wedding on grass a flat is often the smartest choice, because a heel sinks. Choose a pointed slingback or a polished Mary Jane in leather or satin rather than a casual ballet flat, and pair it with a dress that shows the shoe. For black tie, a flat is acceptable if it is unmistakably an evening shoe.

Prefer to browse from your couch? within opens Toronto's boutique shelves on October 1, and the quizzes will read your taste in the meantime.