KO Prime

(617) 772-0202 | View Website

90 Tremont St (Nine Zero Hotel), Boston, MA | Directions   02108

42.596860 -70.967949

Open Hours

Sun 08:00AM - 12:00PM, Mon 06:30AM - 10:00PM, Tue 06:30AM - 10:00PM, Wed 06:30AM - 10:00PM, Thu 06:30AM - 10:00PM, Fri 06:30AM - 10:00PM, Sat 08:00AM - 10:00PM

Restaurants, New American, Seafood  more

More Cuisine: Steakhouse

Price: $$$$

Tags: Bar Scene, Business Breakfast, Business Dining, Date Spot, Dine At The Bar, Fine Dining, Group Dining, Hotel Restaurants, Late Night Dining, Notable Wine List, People Watching, Romantic Dining, Special Occasion Dining, Theater District Dining, View Dining

Payment Methods: American Express, Debit Card, Diners Club, Discover, MasterCard, Travelers Check, Visa


KO Prime
Local Oysters*, Shrimp Cocktail, Ceviche Style, Assiette of Charcuterie, Market Green Salad, Fricassee of Escargot, Cava and St. Germain Steamed Mussels, House Cured Bacon Wrapped Sweetbreads, Caesar Salad, Duet of Foie Gras, Crispy Fried Calamari... more

Reviews for KO Prime

Doesn't Recommend
over a year ago

Don't bring clients here! – I agree with the previous review and had a very similar experience last night while dining with clients at KO Prime. The waiter was not very friendly or attentive. One of my guests had to wait about 10 minutes after everyone else in the party was served to be served his dinner. It's always awkward when everyone else has their hot dinners in front of them and one person does not. After his meal was finally served, we did not see our waiter until after we had all finished our meals. Another person in my group had asked for a medium steak. It was overcooked. When the waiter finally came over to our table and she told him, he seemed annoyed. He then brought a candle to the table to get a closer look and argued that it was not overcooked. In fact, it was medium just like she had requested. I have never been to a high end restaurant where a waiter argued with a guest to prove a point that he was right about how the steak was cooked and the guest was wrong. I will never bring clients here again. It was embarrassing. If you want to impress clients with a nice meal, there are a lot of other steak houses in Boston that give much better service and know how to cook steaks how the customers request. I would suggest going to Capital Grill or Grill 23 next time!

Doesn't Recommend
over a year ago

AVOID AT ANY COST!! don't bring any of your clients unless you want to lose your deal!!! – I've been wondering how come an average of 2.5 star reviews came up to be 4.5 in citysearch summary. That just doesn't add up. We have about 5 people giving this POS place lower than 3 and only 2 giving full 5-star (most likely paid by the restaurant) and the summary says 4.5 star... I think citysearch is not being honest here. What a scam!!!!

Anyways, this is one of the worst high-end restaurants that I've been to (I've been to many great restaurants in Boston, L'espalier, Mistral, Excelsior, Federalist, No. 9 Park, etc). Good thing I was using my expense account. I ordered a steak and I had asked them to cook it MEDIUM. The steak came overcook, it was more like medium well or even well done. It was really dry. For a restaurant that claimed to be a "steak house" they should at least get it right. It was ridiculous!!! I told our waiter that the steak was overcooked and he gave me this annoyed look and suddenly picked up my plate without asking anything. I thought they were going to give me a new one (like a good steak house should) but no, they just cut the steak in the middle (which made it even dry) and showed me this slightly pink middle. well mister waiter, that was definitely not medium. By then I was so annoyed and said "you know I'm starving, let me just have it". I must say that they have some good bar menu and apps. but for steak go somewhere else. I would never set my foot on this restaurant again, and I'll make sure that all of my friends and colleagues know to avoid this place at ANY COST!!!

over a year ago

Decent but nothing exceptional – Upon being greeted the maitre?d offered to check our coats; a nice touch. Seating was prompt and reservations appear to be a must on weekends. The noise level is fairly high providing a level of privacy should you be sitting close enough. The staff were helpful and the service was above average.

As the 3rd person to ask, I was told the bar didn?t carry Pomegranate martinis. They're allegedly in the midst of redoing the cocktail menu and the Pomegranate will be added. The Blackberry Apple and Cherry Cane (as in cane sugar, not candy cane) were both tasty consolations. The tuna tartare appetizer was delicious but the tuna was so finely chopped as to lose its texture. The crabmeat salad was equally delicious; the only detractor being an avocado half with partial slices which broke into several half slices and a big chunk.

We were asked if we wanted still or bubbly water, opting for still, assuming that meant taking chances with Boston's tap water, only to be served a $7.50 bottle of Fuji. The price was not mentioned and discovered upon checking the bill, leaving a taste in the mouth equal to that of Boston?s tap water.

The fillet was topped with a spice mixture and a smidge of vinegar, which complemented it nicely. The 30 oz rib eye had a huge bone attached to it. Neither the menu nor the server mentioned anything about on the bone and it was cooked med-rare instead of medium as ordered; a small sacrifice to avoid someone standing over you asking that you cut into your steak as it's served. It also appeared to have been coated with a veal stock glaze (as the 26 oz T-bone allegedly is). Why would one do that to a fine piece of beef? Our plates were room temp when served; patrons at another table were warned the plates were hot. The sides all sounded delicious; we opted for the pea tendrils and spaetzle; both were tasty but the portions were more for one than two. The Frozen Mint Mousse with liquid chocolate center was a nice way to end an average meal.

over a year ago

Well worth the price – The service was impeccable, knowledgeable and friendly. We just went for a drink and we ended up stay for a couple and trying some of the apps. The drinks were made to perfection. The Steak Tartare was incredible and the Crab Salad was also uber good (a 5 out of 5 for presentation and taste). The ambience was very nice. It definitely has a swanky feel to it. I would highly recommend it.

over a year ago

Ken Oringer's take on an upscale steakhouse, pricey Japanese beef and all, is located in the chic Nine Zero Hotel. – Befitting its location in the chic Nine Zero Hotel, KO Prime's lounge attracts the trendy set to swill designer cocktails. The dining room, chock full of faux cow skins and brown and red hues, hosts an assortment of power brokers and wealthy hotel guests. Sit back and let the attentive servers describe the nuances of purple Okinawa sweet potato. The extensive wine list presents an impressive, and pricey, collection of varietals. With its adventurous ingredients and presentations, KO Prime's bold, aggressive menu defies simple categorization. Crisp "McNuggets" made from veal sweetbreads? Sinfully rich bone marrow with oxtail marmalade? Tender Kobe flat iron steak with romesco sauce? Check, check and check. Much attention is made, and deservedly so, of the astromically-priced Wagyu beef. Priced prettily by the ounce, the meltingly luxurious meat, served as a sliced NY strip, is a carnivore's dream.

Photo by Heath Robbins

over a year ago

Truly outstanding experience – The restaurant that sits where Spire once was has a lot to live up to. KO Prime exceeds its predecessor in every way, and will surely meet with success.

The bar and lounge area is still relaxed and fun, and the drink menu has been updated beautifully. The blackberry mint julep - which requires some courage to order - is one of the better drinks I've ever had. Earthy and not too sweet, it was refreshing without allowing any of the flavors to overpower.

Of course, the true test is the food. Each course was beautifully presented by multiple servers, with just the right amount of styling on the plate to engage the eye without distracting from the flavors. The beet and manchego salad is one you'll never forget, nor be able to replicate at home. An arugula and fennel salad is perfectly balanced and delicious. Main courses rule the day, from perfectly seared, tender and buttery swordfish to duck to a truly Flinstonian-sized ribeye. And for dessert, lose yourself in a rich and delicious chocolate bread pudding.

I recommend this restaurant to anyone looking for an elegant evening in an up and coming fine restaurant. You won't regret taking a chance on KO Prime.

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