Cosette Dress

DELFI Collective

4.5
(36 Reviews)

Product Details

The Delfi Collective Cosette Dress stuns with its elegant pleating and flowy silhouette. Pair it with statement earrings and heels for an effortlessly sophisticated look.

Materials and Measurements

Black (97% Polyester, 3% Spandex). Gown. Halter Neck. Sleeveless. Pull-on. See fit notes for more information. Made in the USA. Country of origin designation as provided by vendor and/or manufacturer.

Size and Fit

Sized: XSR-XLR

The model is wearing a size small long. 

Sizes P Length: 56"
Sizes R Length: 58"
Sizes L Length: 61"

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Ratings &
Reviews

  (36)  

Includes written reviews and customer fit feedback.

Fit
Runs Small
True to Size
Runs Large

All Photos

Size worn:
SL
Overall fit:
True to Size
Rented for:
Other
Usually wears: 4
Height: 5' 9"
Bust size: 34DD
Body type: Hourglass
Weight: 142lbs
Browse Tamra's reviews
May 9th, 2025
Beautiful dress

I rented this dress for the ACM Awards on May 8th and it was perfect! I received so many compliments! The fit was perfect!

Top Contributor
Size worn:
LR
Overall fit:
True to Size
Usually wears: 6
Height: 5' 8"
Bust size: 36B
Body type: Athletic
Weight: 155lbs
Browse Elizabeth's reviews
July 19th, 2025
Elevated black dress

Fun black dress with a little flair

Overall Fit

Just right

Top Contributor
Size worn:
SP
Overall fit:
True to Size
Usually wears: 2
Height: 5' 7"
Bust size: 34C
Body type: Athletic
Weight: 130lbs
Browse Jacqueline's reviews
May 9th, 2025
Engagement Party Dress

Gorgeous dress- received lots of compliments and it was very comfortable. Looked and felt amazing.

Overall Fit

Just right

Arms & Shoulders

Just right

Length

Just right

Top Contributor
Size worn:
MP
Overall fit:
Small
Usually wears: 4
Height: 5' 3"
Bust size: 32D
Body type: Petite
Weight: 120lbs
Browse Vivian's reviews
May 3rd, 2025
Stunning once taped on!

This dress was beautiful but very glad I sized up to the medium. It fit perfectly in the hips but a little loose in the top but nothing a little fashion tape wouldn't fix.

Overall Fit

Runs small

Top Contributor
Size worn:
MR
Overall fit:
True to Size
Rented for:
Wedding
Usually wears: 6
Height: 5' 7"
Bust size: 36D
Body type: Straight & narrow
Weight: 140lbs
Browse Krista's reviews
September 8th, 2025
Sexy chic

Loved the lace detail at the bottom, shows some leg without being too much. The top is also very flattering! Comfy as well

Top Contributor
Size worn:
SR
Overall fit:
True to Size
Rented for:
Wedding
Usually wears: 4
Height: 5' 4"
Bust size: 32D
Body type: Hourglass
Weight: 128lbs
Browse Theresa's reviews
August 24th, 2025
Fun spin on a classic black dress

Wore to a black tie optional wedding at an indoor venue, lots of compliments

Top Contributor
Size worn:
LR
Overall fit:
Large
Rented for:
Wedding
Usually wears: 8
Height: 5' 3"
Bust size: 34D
Body type: Hourglass
Weight: 135lbs
Browse Lisa's reviews
August 22nd, 2025
The top was too big in the medium and large. I had to pin the large to not show too much boob.

The length was perfect in both the medium and large as I am only five foot three. It was great for a night of dancing as I wore it with stilettos, then chunky heels and finally with flip flops.

Size worn:
LR
Overall fit:
True to Size
Rented for:
Wedding
Usually wears: 10
Height: 5' 10"
Bust size: 38C
Body type: Athletic
Weight: 175lbs
Browse Sarah's reviews
August 19th, 2025
Stunning dress! True to size and fit great!

Top Contributor
Size worn:
SR
Overall fit:
True to Size
Rented for:
Wedding
Usually wears: 6
Height: 5' 2"
Bust size: 36C
Body type: Hourglass
Weight: 130lbs
Browse Angela's reviews
July 29th, 2025
Lace Beauty

I got so many compliments on how perfectly the lace was draping around my legs. This design and style was perfect!! I would love to own it!

Size worn:
XSR
Overall fit:
True to Size
Rented for:
Vacation
Usually wears: 2
Height: 5' 5"
Body type: Straight & narrow
Browse Somer's reviews
July 7th, 2025
This LBD does it all!

Size worn:
LR
Overall fit:
True to Size
Rented for:
Wedding
Usually wears: 8
Height: 5' 4"
Bust size: 36B
Body type: Athletic
Weight: 145lbs
Browse Rachel's reviews
June 9th, 2025
Stunning

I got so many compliments on this dress! Would absolutely rent again. I am usually an 8 and wore a medium There’s no zipper, so you need to step in or pull over your head

Size worn:
MR
Overall fit:
True to Size
Rented for:
Wedding
Usually wears: 6
Height: 5' 7"
Bust size: 34B
Body type: Athletic
Browse Jen's reviews
June 4th, 2025
So comfortable and easy to wear.

Finding a bra to wear was a little challenging - ended up using bra tape and it worked great.

Team RTR
Size worn:
SR
Overall fit:
True to Size
Rented for:
Formal Affair
Usually wears: 4
Height: 5' 7"
Bust size: 34B
Body type: Hourglass
Browse Megan's reviews
May 14th, 2025
Great Black Gown - Beware No Zipper

Loved that these straps were adjustable. Definitely not bra friendly with the low back so tightening the straps helps the neckline fit better. The cutouts were low enough that I could wear normal underwear. Also! This dress does not have a zipper so you have to put it on over your head

Top Contributor
Size worn:
XSR
Overall fit:
True to Size
Usually wears: 0
Height: 5' 4"
Bust size: 32C
Body type: Straight & narrow
Weight: 113lbs
Browse Melody's reviews
May 10th, 2025
Gorgeous!

This dress is gorgeous. It fit me like a glove! The straps are adjustable for a perfect fit. The lace panel does show a little more than you want if you’re not careful while sitting, but a strategically place napkin can take care of that. I just rented it a 2nd time!

Top Contributor
Size worn:
MR
Overall fit:
True to Size
Rented for:
Formal Affair
Usually wears: 6
Height: 5' 6"
Body type: Hourglass
Weight: 160lbs
Browse Diandra's reviews
April 20th, 2025
An absolute stunner

Wore to an engagement party. Received so many compliments!

Size worn:
SR
Overall fit:
True to Size
Usually wears: 4
Height: 5' 3"
Weight: 128lbs
Browse Rachel's reviews
June 4th, 2025
Loved!

I am more on the petite size but this fit amazing. The straps are adjustable so it was nice and I can imagine would be helpful for larger chested women too. The see through section is a little cheeky but I loved it!

Overall Fit

Just right

Chest

Runs big

Arms & Shoulders

Just right

Waist

Just right

Hips

Just right

Length

Just right

Top Contributor
Size worn:
MR
Overall fit:
True to Size
Rented for:
Formal Affair
Usually wears: 8
Height: 5' 3"
Bust size: 34C
Body type: Hourglass
Weight: 150lbs
Browse Natalie's reviews
September 2nd, 2025
So fun

Fit TTS - a bit snug and there's no zipper... the lace goes up past the mid thigh but it's fun.

Size worn:
SR
Overall fit:
True to Size
Rented for:
Formal Affair
Usually wears: 2
Height: 5' 4"
Bust size: 32B
Body type: Pear
Weight: 130lbs
Browse RTR Member's reviews
August 7th, 2025
Formal Wedding Guest Dress

Absolutely loved this dress & it fit great. The Straps are adjustable so it works for various bust sizes. FYI there is no zipper on this dress. The only "con" i have is that the lace at the bottom was getting stuck on the straps of my shoe clasp so I did put bandaids over the strap to avoid damaging the lace.

Top Contributor
Size worn:
LR
Overall fit:
True to Size
Rented for:
Work
Usually wears: 10
Height: 5' 7"
Bust size: 36D
Body type: Hourglass
Weight: 160lbs
Browse Stella's reviews
July 26th, 2025
36D great for a formal event

I wore this to a conference farewell dinner party and it was a hit, I'm 5'7 so with heels this was a good length, I wouldn't recommend this for shorter girls or it will drag on the floor. The sheer lace detail made it look more sexy, and I loved the V line that made the collarbone area pop more and gave the fit an edge. Would rent again!

Top Contributor
Size worn:
XSR
Overall fit:
True to Size
Rented for:
Vacation
Usually wears: 0
Height: 5' 4"
Bust size: 32D
Body type: Full Bust
Weight: 115lbs
Browse Lily's reviews
July 24th, 2025
LOVE THIS!!!

Can see a bit higher than you want when sitting if you don't cross your legs so need to wear the right color underwear but otherwise so gorgeous

Top Contributor
Size worn:
LR
Overall fit:
True to Size
Rented for:
Date
Usually wears: 8
Height: 5' 11"
Bust size: 34D
Body type: Hourglass
Weight: 165lbs
Browse Sara 's reviews
June 4th, 2025
Wowwww sexy!!! I usually do a M in delfi, this was VERY form fitting on hips (top a little big)

Top Contributor
Size worn:
XLR
Overall fit:
True to Size
Rented for:
Wedding
Usually wears: 12
Height: 5' 5"
Bust size: 36D
Body type: Apple
Weight: 190lbs
Browse Shanley's reviews
June 1st, 2025
Perfect

Liked it skills much im going to rent it again. The fit was absolute perfect.

Top Contributor
Size worn:
SR
Overall fit:
True to Size
Usually wears: 2
Height: 5' 5"
Bust size: 34B
Body type: Athletic
Weight: 116lbs
Browse Ami's reviews
May 15th, 2025
Classy and sexy

Overall Fit

Just right

Top Contributor
Size worn:
SL
Overall fit:
True to Size
Usually wears: 2
Height: 5' 8"
Body type: Hourglass
Weight: 135lbs
Browse Riley's reviews
July 30th, 2025
super nice but very formal

Top Contributor
Size worn:
MP
Overall fit:
True to Size
Rented for:
Formal Affair
Usually wears: 6
Height: 5' 3"
Bust size: 34B
Body type: Athletic
Weight: 145lbs
Browse Dawnia's reviews
May 26th, 2025
Just sexy enough

Top Contributor
Size worn:
SR
Overall fit:
True to Size
Usually wears: 6
Height: 5' 5"
Bust size: 34C
Body type: Hourglass
Weight: 125lbs
Browse Arpita's reviews
April 28th, 2025
Sexy and edgy but in a subtle way

Top Contributor
Size worn:
LR
Overall fit:
True to Size
Usually wears: 8
Height: 5' 4"
Bust size: 34DD
Body type: Full Bust
Weight: 140lbs
Browse Meagan's reviews
June 28th, 2025
a little shapeless

but it was fine for a date night

Overall Fit

Just right

Chest

Just right

Arms & Shoulders

Just right

Waist

Just right

Hips

Just right

Length

Just right

Size worn:
MP
Overall fit:
True to Size
Rented for:
Wedding
Usually wears: 6
Height: 5' 0"
Body type: Athletic
Browse Juliana's reviews
August 13th, 2025
Nice dress although the lace see through parts were a little revealing when sitting or dancing

Top Contributor
Size worn:
LR
Overall fit:
True to Size
Rented for:
Wedding
Usually wears: 10
Height: 5' 10"
Bust size: 38DDD/E
Body type: Athletic
Browse Barker's reviews
June 12th, 2025
So pretty

This dress was great. The straps were adjustable. The lace is fun but be careful that it does come up high on your leg and when you are sitting you need to be aware.

Size worn:
MR
Overall fit:
True to Size
Rented for:
Wedding
Usually wears: 6
Height: 5' 7"
Body type: Athletic
Weight: 140lbs
Browse Christina's reviews
June 2nd, 2025
LOVE

so beautiful and flattering. I got so many compliments. The only thing I didn’t like is that when I sat, I had to cover my lap bc it was a bit revealing due to the lace.

Size worn:
MR
Overall fit:
Large
Rented for:
Wedding
Usually wears: 4
Height: 5' 4"
Bust size: 32C
Body type: Hourglass
Browse Erica's reviews
April 28th, 2025
Perfect black tie wedding guest dress

I loved this dress! It was so comfortable, easy to sit and dance in. Only minor complaint is the halter top was a little loose, but the straps are adjustable so was able to tighten it a bit. Dress stands out at a black tie wedding being unique with the lace cut outs!

Top Contributor
Size worn:
SR
Overall fit:
True to Size
Usually wears: 4
Height: 5' 7"
Bust size: 34B
Body type: Athletic
Weight: 130lbs
Browse Rachel's reviews
April 22nd, 2025
Revealing

I expected the sheer parts of the dress to be revealing, as you could see that in the photos, but when I sat down the top sheer line revealed my underwear, therefore I had to cover the area with my purse or a napkin every time I sat, then had to make sure I yanked it down every time I stood up. But the dress is very unique and lightweight - good for a summer black tie wedding.

Overall Fit

Just right

Top Contributor
Size worn:
MR
Overall fit:
Small
Usually wears: 6
Height: 5' 8"
Bust size: 34C
Body type: Athletic
Weight: 150lbs
Browse Marlaina's reviews
July 18th, 2025
Didn’t fit

Hard time fitting the straps high enough to support boobs but then slit too high on bottom. Weirdly tight in hips but loose in other areas

Top Contributor
Size worn:
XSR
Overall fit:
True to Size
Rented for:
Wedding
Usually wears: 0
Height: 5' 7"
Bust size: 32A
Body type: Hourglass
Weight: 125lbs
Browse Erin's reviews
July 5th, 2025
Be prepared when sitting

The lace cut out go quite high and I looked down sitting very exposed.

Top Contributor
Size worn:
SR
Overall fit:
Small
Usually wears: 4
Height: 5' 6"
Bust size: 34C
Body type: Hourglass
Weight: 149lbs
Browse Sharleen's reviews
May 29th, 2025
Ran too small couldn’t wear it

Top Contributor
Size worn:
SR
Overall fit:
Small
Rented for:
Other
Usually wears: 4
Height: 5' 4"
Bust size: 34B
Body type: Hourglass
Weight: 133lbs
Browse RTR Member's reviews
April 24th, 2025
Too revealing for my event

I didn't end up wearing this dress. Although pretty, the lace detail goes up VERY high on the hip and I felt it was not appropriate for a formal wedding. It is sexy and might be ok for a different occasion! The fit didn't work for me either - the small was a little too tight in the hips, the medium too large on the top. Overall, just not the right dress for me. RTR provided great customer service and sent out a new dress very quickly, which I love!

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