Siena | Sophisticated Midi Dress

Name: Siena | Sophisticated Midi Dress
Brand: Millie's Boutique
Price: 29.95 GBP
Availability: OutOfStock

£29.95 £70.00 RETIREMENT Sale!

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Color — White Blue

White Blue

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RETIREMENT SALE ENDS TODAY

UP TO 60% OFF

Now is the time to shop your favourite items at irresistible prices. As long as stocks last!

Designed for the modern woman, this midi dress is an ode to simplicity and sophistication. Its effortless drape and timeless shape ensure enduring appeal. Perfect for those who appreciate refined, effortless luxury.

Sophisticated Look: Instantly elevates your everyday style
Fluid Silhouette: Moves beautifully with natural ease
Comfort with Class: Combines elegance and relaxation
Timeless Versatility: A must-have for any elegant wardrobe

Size Bust (in) Shoulder (in)

XS 34.25" 14.17"

S 36.22" 14.96"

M 38.19" 15.35"

L 40.16" 15.75"

XL 42.13" 16.14"

2XL 44.09" 16.54"

3XL 46.06" 16.93"

Size	Bust (in)	Shoulder (in)
XS	34.25"	14.17"
S	36.22"	14.96"
M	38.19"	15.35"
L	40.16"	15.75"
XL	42.13"	16.14"
2XL	44.09"	16.54"
3XL	46.06"	16.93"

We ship using a secure premium shipping method, including tracking, so you can rely on the most reliable service. Currently, we offer this premium shipping for free, take advantage of this offer while it's available!

Doesn't fit? No problem! You can exchange or return it anytime, with a 30-day return policy.

combine and receive up to 20% extra off

Kind words from women who shopped with me

Excellent 4.7/ 5 ★ ★ ★ ★ ★

More than 1500 + reviews

★★★★★
Millie’s Boutique feels so refreshing compared to most online stores. The dresses are elegant and flattering, but what impressed me most was the attention to detail. Everything arrived beautifully packaged and exactly as shown on the website. It genuinely feels like a boutique that cares about its customers.
Sarah T.
Bath, UK

★★★★★
I’ve ordered from quite a few boutiques online, but Millie’s Boutique really stands out. The quality of the dress exceeded my expectations and the fit was perfect. It arrived quickly and looked even better in person. I’ve already had so many compliments wearing it.
Emma L.
Leeds, UK

★★★★★
Shopping at Millie’s Boutique was such a lovely experience. The pieces are timeless and feel very thoughtfully designed. My order arrived carefully packaged and the fabric quality was wonderful. It’s rare to find an online boutique that feels this personal.
Rebecca H.
Cheltenham, UK

★★★★★
I absolutely love Millie’s Boutique. The dress I ordered fits beautifully and feels incredibly comfortable. You can tell a lot of care goes into the designs and the overall experience. It truly feels like discovering a hidden boutique gem online.
Charlotte W.
York, UK

★★★★★
Millie’s Boutique has quickly become one of my favourite places to shop online. The styles are elegant and easy to wear, and the quality is far better than most online shops. My order arrived exactly as described and beautifully presented.
Olivia B.
Cambridge, UK

Frequently asked questions

Yes, we offer Free Premium Shipping on all orders. Every order includes tracked delivery, because we want your Millie's Boutique pieces to reach you quickly and safely.

Once your order ships, you will receive a tracking number by email. Simply enter it on our Track Your Order page to view real-time updates.

Orders are typically processed within 1–3 business days. Delivery times may vary depending on your location and seasonal demand, but you will always receive tracking updates by email.

Absolutely. You may return your order within 30 days of receiving it. All items must be unworn, unwashed, and in their original condition.

Each product includes a detailed size chart to help you pick the best fit. If you’re between two sizes, we recommend going one size up for extra comfort. Still unsure? Our customer support team is happy to assist you.

You can check out securely using: PayPal, Visa, Mastercard, American Express, Apple Pay, Google Pay, Maestro, and Shop Pay.

Yes — as soon as your order is placed, you’ll receive an order confirmation email.
If you don’t see it, please check your spam folder or reach out to our support team.
We’re always here to help.

My name is Millicent, but everyone has always called me Millie. For many years, I opened the doors of my little boutique with the same key and the same smile.

At Millie’s Boutique, every piece was chosen with care and with people in mind. What began as a small shop became a place filled with familiar faces, shared stories, and moments I will always treasure.

One afternoon, my granddaughter Lily looked at me and asked,
“Grandma, why do we see you so little?”

That question stayed with me.

So I made the decision to close the doors of Millie’s Boutique and step into a new chapter — one where my days are spent with my children, my grandchildren, and the moments that matter most.

To thank every woman who supported this journey, I’m offering up to 60% off this week.

Final quantities are available.

With love and gratitude,
Millie

FREE SHIPPING

At Millie's Boutique, you always enjoy free shipping on all your orders.

30-Day Return Guarantee

Shop with confidence. You have 30 days to return or exchange your item.

SECURED PAYMENT

You always pay with peace of mind thanks to our trusted payment partners.