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Portia and Scarlett XO313 Fitted Hot-Stone Sweetheart Gown
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Stick-on bra
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$20 CAD
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Keeps necklines in place all night
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Description
About the Dress: Portia and Scarlett XO313
The Portia and Scarlett XO313 is a long fitted gown built for maximum impact. It opens with a sweetheart neckline and a keyhole cut-out beneath the bust, framed by side cut-out panels in the bodice. Hot stones are scattered across the full length of the dress from top to hem, catching light with every move. A sweep train finishes the silhouette at the back.
Fit & Silhouette
The Portia and Scarlett XO313 is cut to follow the body closely through the bust, waist, and hips. The jersey base fabric has natural stretch, which allows the dress to move with you rather than against you. Ruching at the waist pulls the fabric in at the stomach and creates a smooth, flattering shape through the midsection. The high slit at the side gives room to walk and adds a dramatic leg-baring element. Thin spaghetti straps run from the sweetheart cups over the shoulders and cross into a crisscross lace-up back construction. The back is almost entirely open, with only the thin crossing straps across it, making this one of the most exposed-back styles in the Portia and Scarlett line.
Fabric & Detail
The base of the XO313 is a stretch jersey, which is one of the most forgiving fabrics for a body-conscious cut — it holds its shape, resists wrinkling, and travels well. The hot-stone surface treatment covers the dress from neckline to hem, with a denser concentration in the bodice and a lighter scatter down the skirt. This is a stone-set finish, not a glitter coating, so each stone sits flush with the fabric rather than sitting on top. The result is a subtle sparkle that reads as refined rather than flashy under stage or event lighting.
Key Features
- Sweetheart neckline with keyhole cut-out beneath the bust
- Side cut-out panels in the bodice
- All-over hot-stone embellishment from bodice to hem
- Ruching at the waist and stomach area
- Spaghetti straps feeding into a crisscross lace-up back
- Near-full open back from shoulders to low back
- High side slit for ease of movement
- Sweep train at the back hem
- Stretch jersey base for all-night comfort
Style & Occasion
The Portia and Scarlett XO313 is built for prom, pageants, formal galas, and evening events where a bold, body-forward look is the point. The combination of the sweetheart neckline, open back, and high slit positions this squarely in the category of statement formal wear — not understated, but not overdone either. The all-over hot stones keep the dress sparkling under any lighting without relying on loud print or color. It is available in Aqua, Black, Fuchsia, Lt. Blue, Periwinkle, Red, and Yellow. Lighter neutrals like Aqua, Lt. Blue, and Periwinkle will read softer and more ethereal under stage lighting. Red and Fuchsia are vivid and high-contrast. Black is the most versatile option for repeat wear after the primary event. Pair with strappy heeled sandals, minimal jewelry — the stones do the work — and a small clutch. An updo or sleek pulled-back style works best to show off the open back.
Size & fit
- Fitted. Bust, waist and hips all matter. Go by your largest measurement.
- Between sizes? Text a stylist and we'll help you choose.
Shipping
- Arrives in 7–12 business days, or 4–6 with Express (+$35).
- Free shipping over $250 to Canada and the USA.
- Text updates as your order ships.
Full shipping details
Your Dress — Delivered in Days, Not Weeks.
We know timing matters — especially for prom, weddings, quinceañeras, and special events.
- Receive your dress within 7–12 business days, depending on designer availability.
- You’ll receive text updates as your order moves from processing to shipping.
- Once shipped, delivery typically takes 2–5 business days within North America.
Need it sooner?
We offer rush options where you can receive your dress within 4–6 business days. Text us at +1 416-536-2956 before ordering and we’ll confirm the fastest possible delivery date.
We are an authorized retailer of top designers, which means your dress ships brand new and directly from the designer or our showroom — never used, never rented.
Have an event date? Add it in your order notes so we can prioritize accordingly.
We proudly ship across Canada, the United States, and Internationally, with in-store pickup available at our Toronto showroom.
Returns
- Tell us within 5 days of delivery.
- 100% store credit, a one-time exchange, or a refund (30% restocking fee).
- Online purchases only; in-store purchases are final.
Full return policy
WE ACCEPT RETURNS!
For Online Purchases Only. All in-store purchases are FINAL.
We hope you LOVE your dress — but if you're not completely satisfied with your online purchase, you may request:
- 100% Store Credit (no expiration).
- A one-time exchange, OR
- A return with a 30% restocking fee, OR
You must notify us of a return within 5 days of delivery (including weekends and holidays — we are open 7 days a week).
We have no control and accept no responsibility for the sizing selected. Please carefully review the size chart before ordering. If you need assistance with sizing, we’re happy to help — text us at +1 416-536-2956.
ORDER CHANGES & CANCELLATIONS
Once your order is placed, you have 5 hours to request a change to the color, size, or style.
If an item becomes unavailable, we will offer alternatives or provide the option of a full refund for that item.
Please see our Returns & Exchanges page for full details.
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Free standard shipping on orders over $250 to the US and Canada. Under $250, shipping is shown at checkout.
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US orders ship from our warehouses in Los Angeles, Chicago and New York. Canadian orders ship from Toronto. No duties to pay at the door.
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Portia and Scarlett XO313 Fitted Hot-Stone Sweetheart Gown with Train
Sale price $929 CAD
Need help?
Frequently Asked Questions
The XO313 uses a crisscross lace-up back construction. Thin spaghetti straps run from the sweetheart bodice over each shoulder and then cross at the back, threading into a lace-up system that runs down most of the back panel. This design does two things at once: it holds the dress on your body and allows you to micro-adjust the fit across the back after the gown is on.
To put the dress on, loosen the lacing completely before stepping in. Once the dress is on and sitting correctly at the sweetheart cups, have a second person pull the lacing from the bottom loop upward, tightening section by section rather than pulling from the top all at once. This distributes tension evenly and avoids bunching at the shoulder blades. Once the lacing feels snug but not tight, tie it off with a bow or tuck the ends.
Because the back is almost entirely open — the lacing sits against bare skin — the fit of the front bodice is doing most of the structural work. The sweetheart cups need to sit flush against the chest without gaping. If the cups gap, the lacing at the back needs to come in further. If the fabric across the chest feels stretched or the cut-out at the center keyhole is pulling, the lacing is too tight.
The stretch jersey base helps here. Unlike a rigid brocade or satin, jersey will give slightly rather than create hard pressure points when the lacing is adjusted. Most customers find they can wear the XO313 without additional alterations to the back as long as they size correctly in the bust and hips.
One practical note: because the back is nearly fully open, you will not be able to wear a traditional bra with this dress. The lacing itself acts as the back anchor. Built-in cups in the bodice provide the front support. If you need additional support, low-tack fashion tape can secure the cups to the chest, and a reusable adhesive bra (strapless, backless style) can work under the sweetheart front. Plan for this before the event rather than on the night.
If you have questions about sizing or want help deciding between two sizes based on your measurements, our concierge team is happy to help — text or WhatsApp us at +1 416-536-2956 or +1 213-868-3131.
The XO313 is designed for events where a bold, body-forward look is appropriate and expected. It works best at prom, formal pageants, evening galas, and high-energy formal dances where the dress is part of the performance of the night.
For prom specifically, this is a strong choice. The hot-stone embellishment catches light on a dance floor, the high slit gives freedom of movement, and the open back creates the kind of reveal moment that reads well in photos. If your school has a dress code that restricts back exposure, check the specific guidelines — the XO313 back is nearly fully open, which some venues flag.
For pageants, the XO313 checks the key boxes: full-length, embellished, dramatic silhouette, stage presence. The hot stones photograph well under competition lighting, and the fitted silhouette reads clearly from a distance. This is a dress that works on a runway or stage, not just in a photo studio.
For formal evening events — galas, award ceremonies, charity events, upscale birthday celebrations — the XO313 works if the dress code is cocktail-formal or black-tie optional and the event culture is fashion-forward. For more conservative black-tie events, pairing it with an elegant wrap or tailored cover-up can help tailor the look to a traditional dress code.
This dress is not suited for mother-of-the-bride or mother-of-the-groom occasions. The exposed back and body-conscious fit position it as a young, fashion-forward style, not a formal wedding-celebration look. As a wedding guest, the open back, keyhole cut-outs, and high slit make it best suited to evening receptions and black-tie celebrations rather than more conservative ceremonies.
For military balls or formal dinners with covered-back requirements, this is not the right gown. The near-full open back disqualifies it for venues or events that require modest back coverage.
If you are shopping this for a specific event and are not sure whether the style is appropriate, our team can help you think through it. The short version: if the event culture expects glamour and individual expression, the XO313 delivers. If the event calls for restrained formality, consider a different silhouette.
The XO313 runs consistent with Portia and Scarlett's standard sizing, which tends to align closely with US dress sizing for most customers. The most important measurements for this gown are bust, waist, and hips. Because it is a fitted jersey dress, the fit through all three points matters — you cannot compensate for a size mismatch in the hips by sizing up in the bust the way you might with a structured ballgown.
Measure your bust at the fullest point, your waist at the narrowest point (usually an inch above the navel), and your hips at the fullest point around the seat, usually about seven to nine inches below the waist. Compare all three measurements against the Portia and Scarlett size chart. If your measurements fall between sizes, size up — the lace-up back gives you some room to take in the fit at the back, but the jersey front cannot be let out.
Customers with a larger hip-to-waist ratio often find the XO313 fits best when sized to the hips, with the waist area taken in slightly by a tailor if needed. This is a common and straightforward alteration on stretch jersey.
The ruching at the waist also helps: gathered fabric at the stomach area naturally creates visual definition and accommodates a small range of waist measurements within the same size.
Traditional bras are not compatible with this dress. The near-full open back and spaghetti strap construction mean there is no place to hide a bra band. The built-in sweetheart cups in the bodice provide the primary front support, so for most cup sizes up to a C or small D, the cups alone are sufficient.
For additional support, the most practical option is a backless, strapless adhesive bra in a nude or skin-tone color. These sit inside the sweetheart cups and give an extra layer of lift without any visible straps or band. Look for a silicone-backed reusable style — they hold better against skin than fabric-backed disposable versions.
For the front cut-outs and keyhole detail, fashion tape along the interior edges of the panels keeps everything in place through a long night, especially on a dance floor. Apply the tape to the dress, not the skin, where possible — it is easier to remove at the end of the night.
For underwear, seamless thongs or no-show briefs in your skin tone are the standard choice with body-con jersey. The stretch fabric will show any seam line.
Shapers and smoothing shorts can work under the skirt portion if desired, as long as they sit below the high slit line. A shaper that hits mid-thigh or higher may be visible when sitting or moving, so choose a style that ends well above where the slit opens.
Yes, the XO313 can be altered. The stretch jersey fabric is workable for an experienced tailor, though it requires a serger or a stretch stitch rather than a standard straight stitch. Bring the gown to a tailor who has worked with jersey or stretch knit formalwear.
For hemming: the sweep train adds length at the back. If you are petite — roughly under 5'4" in heels — you may want to shorten both the front and the train to avoid dragging. Standard bustle alterations work on the train. For the front hem, a tailor will typically shorten from the waistband rather than the hem to preserve the slit proportions.
For taller customers — 5'9" and above in heels — the dress will sit at a more natural train length with minimal pooling. The front slit will fall slightly higher on the thigh, which is usually an advantage for movement.
For the bodice: the lace-up back allows the most natural fitting at the back. Side seam adjustments to the jersey body are the most common alteration for taking in the waist or hips.
Build in time. Allow at least three to four weeks before the event for a fitting, an alteration, and a second check fitting. Rush tailoring on beaded or embellished jersey adds cost and risk — plan ahead.
For a fitted gown, the XO313 is one of the more comfortable options in its category. The stretch jersey base is the main reason — it moves with you rather than creating resistance when you sit, walk, or dance. There are no boning channels, no rigid structure panels, and no heavy underskirt weight pulling at the waist.
The high slit is a major advantage for dancing. A fitted gown without a slit restricts stride and can make fast movement difficult. The XO313's side slit removes that restriction — you can move freely without pulling at the fabric.
The lace-up back is worth noting for comfort: if it is tied too tightly, you will feel it across the back after a few hours. Tie it snugly enough to hold, but leave just enough give that you can take a full breath comfortably. The jersey will compress slightly over a long night — having a friend available to loosen it slightly mid-event is useful if needed.
The sweep train at the back is the main thing to be aware of when navigating a crowded venue. On a dance floor it will move with you, but in tight corridors or on stairs, you may want to hold it or use a small bustle pin to keep it off the ground between wearing areas.
The three photographed colorways — Red, Yellow, and Fuchsia — give a good baseline for how the hot stones read under different color saturation levels. The stones are consistent across all colors; what changes is how the base jersey absorbs and reflects light.
Red is a saturated, true red — not burgundy, not orange-red. It photographs vividly and reads well under event lighting. In person, the stones on red create a warm, high-contrast sparkle.
Fuchsia is the most electric of the photographed options. It is a bright, cool pink. Under stage or venue lighting it reads intensely — this is a color that announces itself from across a room.
Yellow is warm and bold. It photographs brightly and reads as a statement color in person. It is less common in formal gowns, which makes it a strong choice if you want to stand out in a group setting.
For the unphotographed colorways: Aqua and Lt. Blue are cooler tones that will read more ethereal under venue lighting. Periwinkle sits between blue and lavender and tends to photograph softly. Black is the most versatile — the stones read as silver against the black base, giving the dress an entirely different energy that reads more evening-wear than party-wear.
If you are choosing for prom and want to avoid matching another attendee's dress color, Black and Periwinkle are statistically less common prom choices in this silhouette.
Jersey is one of the easiest formal fabrics to care for in terms of wrinkle recovery — it bounces back well after being packed or hung. The hot stones require more attention.
For cleaning: spot clean where possible. If a full clean is needed after wearing, take it to a dry cleaner with experience in embellished formalwear. Mention the stone-set surface specifically — hot stones can loosen under high heat or aggressive agitation, which rules out machine washing and home steam cleaning directly on the stones.
For storage: hang the dress on a padded hanger rather than a wire hanger, which can stretch the jersey at the shoulder points. If storing long-term, fold loosely in acid-free tissue paper and lay flat in a garment box. Do not compress the hot-stone areas under weight.
For travel: roll loosely inside out in a breathable garment bag rather than folding flat. The jersey will release any travel creases within thirty to sixty minutes of hanging. Avoid plastic garment bags for long trips — they trap moisture against the fabric.
If a stone comes loose after the event, a small bottle of fabric or gem adhesive from a craft store will re-set it. Test on an interior seam allowance first before applying to the visible surface.