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Firm Control Secret Slimming™ Full Slip

Product code: T325931A

About this style

Sculpt your silhouette with this Secret Slimming™ full slip shapewear. The innovative microfibre fabric provides firm control to shape your body, tummy, waist and hips while remaining lightweight and comfortable. A regular fit that sits just above the knee offers complete coverage, with no visible knicker lines to disrupt your outfit. Pull-on styling and non-wired support make this M&S Collection lingerie undergarment effortlessly practical for everyday use. M&S Collection: Easy-to-wear wardrobe staples that combine classic and contemporary styles.

Please don’t worry if the packaging name looks a little different, it’s still the same colour, our packaging just takes a little longer to update. Opaline formerly known as Almond.

M&S

Firm Control Secret Slimming™ Full Slip

€38

Colour

Size

Free standard delivery over €75

Reviews (388)

4.0

59% Recommended this product

Mentions
03 March 2026Happy swim

Does the job!

Originally posted on marksandspencer.com (UK)

Usually a size 10 overall but 12 on top. Opted for size 12 and does the job perfectly. Step into it… you won’t get it over your head. Doesn’t ride up.

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

26 February 2026Jackie1alex

Not for me

Originally posted on marksandspencer.com (UK)

No, I don't recommend this

Sizing way off and not flattering. Sadly returned.

Helpful?

09 February 2026Beechtree

Quality

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Great product, gives such lovely smooth sleek shape, it’s so comfy too, highly recommend

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

23 December 2025Tellitlikeiti5

Tellitlikeitis

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Great fit and did what it's meant to. I felt great in my fitted party dress!

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

20 December 2025Col23

Just what I needed

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Does the job, was comfy to wear under my Christmas dress

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

03 December 2025spital

Excellent goods

Originally posted on marksandspencer.com (UK)

Really pleased with this. Excellent service as always. Keep doing what you’re doing.

Helpful?

22 November 2025Happy 60

Happy 60

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Comfortable on nice length good for the money.....

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

02 November 2025Sleepwell106

Good quality garment

Originally posted on marksandspencer.com (UK)

Very tight to get on. Had to pull it upwards not down

Reviewer Ratings

How do you feel about the size?

Small

Helpful?

Reviewer Ratings

How do you feel about the size?

Small

28 October 2025Supersweet

Rides up terribly!

Originally posted on marksandspencer.com (UK)

I had high hopes of this. I sized up ( as I usually do with shapewear) so went up to a size 16, normally a 12-14. Tried it on and it gave me a great smooth silhouette. Put my jersey dress on and I felt great. It smoothed across my back, stomach and tops of my thighs and gave me a lovely toned look in my dress and was comfortable. However on wearing it in the real world and walking a few paces I found it just kept riding up. So much so that I was aware that the skirt part was up around my buttocks under my dress.Quite embarrassing So disappointed. No way would this stand up to an evening out unless you didn’t move. It wouldn’t hold up to dancing. The only way of solving it would be to go up two sizes and then there would be no benefit from the shapewear aspects. Terribly dissapointed. The one I’d ordered in another colour has gone straight back. Unless you are prepared to keep sticking your hand up your skirt and pulling it down or are just sitting down and not walking at all, sadly I would give it a miss.

Reviewer Ratings

How do you feel about the size?

Small

Helpful?

Reviewer Ratings

How do you feel about the size?

Small

23 October 2025princessarand

Does the job but boobs disappear!

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Really gives a lovely shadow for wearing dresses if fitted items of clothing. I don’t find it overly ‘firm’ control but it does give a smooth silhouette. But it does also flatten your boobs and not in an uncomfortable way but the curves disappear!

Reviewer Ratings

How do you feel about the size?

A bit small

Helpful?

Reviewer Ratings

How do you feel about the size?

A bit small

06 October 2025Amlucas

Fits well

Originally posted on marksandspencer.com (UK)

fits well, difficult to take of due to snugness of fit. Otherwise happy with product

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

03 October 2025katzh

GREAT PRODUCT AT A GREAT PRICE!! Easy to wear.

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

GREAT PRODUCT AT A GREAT PRICE!! Easy to wear, versatile.

Reviewer Ratings

How do you feel about the size?

A bit small

Helpful?

Reviewer Ratings

How do you feel about the size?

A bit small

28 September 2025AndewsJones

Perfect for the job

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Believe it or not, I brought this full slip for my 87 year old mother who is very thin but has a hernia, this garment was a gamble but it worked wonders for her, supporting the hernia without wearing a belt. ☺️

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

13 April 202555Abbey

Useful slip

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

For me it is not particularly slimming, but I just wanted something to wear under a lace dress that is slightly transparent and this ticks the box. I am hoping it does not ride up, but as yet I have not worn it so can't comment.

Reviewer Ratings

Quality

Good

Value for Money

Good

Style

Good

How do you feel about the size?

A bit small

Helpful?

Reviewer Ratings

Quality

Good

Value for Money

Good

Style

Good

How do you feel about the size?

A bit small

11 April 2025CraftyJane1

Nice quality but didn’t work

Originally posted on marksandspencer.com (UK)

Not easy to get on and didn’t give a smooth finish. Disappointing as M&S are my Go To for all things lingerie.

Reviewer Ratings

Style

Fair

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Style

Fair

How do you feel about the size?

True to size

12 March 2025Kathryn 59

Good wardrobe staple

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Excellent slip, great value and a must in any girl’s wardrobe

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How do you feel about the size?

True to size

22 February 2025Patsy11130

Good overall.

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Ideal to wear under a dress and feel slimmer! looks and feels great.

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Average

How do you feel about the size?

A bit small

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Average

How do you feel about the size?

A bit small

16 February 2025Fabsuz

Not sure

Originally posted on marksandspencer.com (UK)

So far the fit won’t stay but I didn’t wear it long enough to find out if I had to keep pushing the garment down.

Reviewer Ratings

Value for Money

Good

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Value for Money

Good

How do you feel about the size?

True to size

06 February 2025Aoife

Disappointing

Originally posted on marksandspencer.com (UK)

No, I don't recommend this

Having read the reviews I sized up. It was difficult to put on. My own size would have been uncomfortable and I suspect would still not have 'smoothed' or 'slimmed' anything. The material is not as firm as you would expect even though it said firm control on the packaging. The slip is not long enough and I'm not tall so I do think M&S need to address this issue. It felt as if it would ride up. Disappointing because I can see from reviews that others are satisfied, but I saw no benefit to wearing this item, so I'm returning it.

Reviewer Ratings

Quality

Fair

Value for Money

Fair

Style

Fair

Helpful?

Reviewer Ratings

Quality

Fair

Value for Money

Fair

Style

Fair

29 January 2025SRRR

Pleased customer

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

I am a size 8 and after reading reviews, ordered a size 10. Fitted snugly. I stepped into it which made getting it on easier. Very pleased. No riding up either.

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How do you feel about the size?

Small

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How do you feel about the size?

Small

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