Show prices in

Choose a currency for your trip.

More currencies

More crypto

Find your next stay

Apparteo Bordeaux

Bordeaux · France

30 Cours Henri BrunetView location

7.4/10Very good138 Reviews
Cleanliness8.0/108.0
Service6.8/106.8
Comfort7.4/107.4
Condition8.0/108.0
Location6.0/106.0
Neighborhood6.6/106.6
Value9.4/109.4
Amenities7.0/107.0
See all ratings
Check availability Pay with crypto or card

Room prices, availability, meal plans and cancellation terms are confirmed for your selected dates.

About Apparteo Bordeaux

Opened in September 2016, this residence of the Apparteo group offers a turnkey accommodation solution, offering the functional comfort of a soberly elegant apartment and hotel services to facilitate the stay. Located near the Bassins afloat, it will be a convenient pied-à-terre to visit Bordeaux and its region.

There is also a gym and private parking.

Read more about this hotelShow less

Located in Bordeaux (Quartier du Lac), Apparteo Bordeaux is within a 5-minute drive of Cap Sciences and Submarine Base of Bordeaux. This aparthotel is 0.7 mi (1.2 km) from Cité du Vin and 1.4 mi (2.2 km) from Bordeaux Wine and Trade Museum.

Make yourself at home in one of the 145 guestrooms, featuring kitchenettes with refrigerators and stovetops. Complimentary wireless internet access keeps you connected, and digital programming is available for your entertainment. Conveniences include safes and desks, and housekeeping is provided daily.

Featured amenities include laundry facilities, a safe deposit box at the front desk, and an elevator. Self parking (subject to charges) is available onsite.

Popular amenities

Parking available
Laundry
Gym
Non-smoking
Accessible facilities

Check-in and check-out

Check-in from 3:00 PM
Check-in until 6:00 PM
Check-out until 11:00 AM
Minimum check-in age 18

Hotel policies

Beach nearby No rollaway/extra beds available Professional property host/manager Pets not allowed

Cleaning and safety

Sanitization
Property uses a professional cleaning service Contactless check-in is available Contactless check-out is available Property follows sanitization practices of Sanitary Protocol (UNPLV - France)

Important information

  • Property Alerts

    You'll be asked to pay the following charges at the property. Fees may include applicable taxes:

    • 7.2 percent tourism fee will be charged

    We have included all charges provided to us by the property.

  • You need to know
    • Cash transactions at this property cannot exceed EUR 1000, due to national regulations. For further details, please contact the property using information in the booking confirmation.
    • The property is professionally cleaned.
    • Contactless check-in and contactless check-out are available.
  • Special Instructions
    The front desk is open during the following times:
    • Monday - Friday: 9 AM - noon
    To make arrangements for check-in please contact the property at least 72 hours before arrival using the information on the booking confirmation. If you are planning to arrive after 6:00 PM please contact the property in advance using the information on the booking confirmation. Guests planning to arrive outside of normal check-in hours must contact the property in advance for check-in instructions and key retrieval information. Front desk staff will greet guests on arrival at the property. For any questions, please contact the property using the information on the booking confirmation. Information provided by the property may be translated using automated translation tools.
  • Instructions
    • Extra-person charges may apply and vary depending on property policy
    • Government-issued photo identification and a credit card, debit card, or cash deposit may be required at check-in for incidental charges
    • Special requests are subject to availability upon check-in and may incur additional charges; special requests cannot be guaranteed
    • This property accepts credit cards; cash is not accepted
    • This property reserves the right to pre-authorize the guest's credit card prior to arrival.
    • Host has not indicated whether there is a carbon monoxide detector on the property; consider bringing a portable detector with you on the trip
    • Host has indicated there is a smoke detector on the property
    • Safety features at this property include a fire extinguisher
    • This property is professionally cleaned
  • Minimal age
    18
  • Optional fees
    • Self parking fee: EUR 12 per day

    The above list may not be comprehensive. Fees and deposits may not include tax and are subject to change.

  • Spoken Language

    English

    French

Nearby attractions

Cité du Vin 1.1 km / 0.7 mi
Jacques Chaban Delmas Bridge 1.4 km / 0.9 mi
Cap Sciences 1.4 km / 0.9 mi
Submarine Base of Bordeaux 1.5 km / 0.9 mi
Quai des Marques 1.9 km / 1.2 mi
Bordeaux Wine and Trade Museum 2.3 km / 1.4 mi
Aushopping Bordeaux Lac 2.6 km / 1.6 mi
Plage du Lac 2.8 km / 1.7 mi
Caliceo Aquatic Center 3 km / 1.9 mi
Jardin Public 3.3 km / 2 mi
Contemporary Art Museum 3.3 km / 2 mi
Darwin Eco-Système 3.3 km / 2.1 mi
Les Quais 3.5 km / 2.2 mi
Aquitaine Bridge 3.5 km / 2.2 mi
Quinconces Square 3.6 km / 2.2 mi

Hotel facilities & services

Services and fees can vary. Check the selected room details and hotel policies before booking.

  • Total number of rooms: 145
  • hotel
  • Car parkExtra charge
  • Check-in hour
  • Check-out hour
  • Wi-fi
  • Laundry service
  • LaunderetteExtra charge
  • Smoke detector
  • Lift access
  • Gym
  • Newspapers
Show 5 more facilities & services
  • Breakfast room
  • Breakfast
  • Non-smoking establishment
  • Minimum check-in age: 18
  • Fitness
Upon availability

Room types

These are the hotel's room types, rather than live offers. Choose your travel dates to see available rooms, prices and booking conditions. Check availability

  • TWIN STANDARDTWIN • STANDARDTWN.ST-1

    Photos are not available for this room type.

    Apparteo Bordeaux

    TWIN STANDARD

    Room photos

    Photos are not available for this room type.

    Room overview

    Occupancy
    Guests: 1–4 • Adults: max. 4 • Children: max. 3
    Room type
    TWIN
    View / characteristic
    STANDARD

    Adult and child limits apply within the room's total guest limit.

    Room code: TWN.ST-1

    Limited room details from hotel

    Available rooms, prices and included facilities are confirmed after you choose your dates and rate.

  • STUDIO TWO BEDSSTUDIO • TWO BEDSSTU.2B

    Photos are not available for this room type.

    Apparteo Bordeaux

    STUDIO TWO BEDS

    Room photos

    Photos are not available for this room type.

    Room overview

    Occupancy
    Guests: 1–5 • Adults: max. 5 • Children: max. 3
    Room type
    STUDIO
    View / characteristic
    TWO BEDS

    Adult and child limits apply within the room's total guest limit.

    Room code: STU.2B

    Limited room details from hotel

    Available rooms, prices and included facilities are confirmed after you choose your dates and rate.

  • STUDIO AccessibleSTUDIO • AccessibleSTU.H6

    Photos are not available for this room type.

    Apparteo Bordeaux

    STUDIO Accessible

    Room photos

    Photos are not available for this room type.

    Room overview

    Occupancy
    Guests: 1–5 • Adults: max. 5 • Children: max. 3
    Room type
    STUDIO
    View / characteristic
    Accessible

    Adult and child limits apply within the room's total guest limit.

    Room code: STU.H6

    Limited room details from hotel

    Available rooms, prices and included facilities are confirmed after you choose your dates and rate.

  • STUDIO SUPERIORSTUDIO • SUPERIORSTU.SU

    Photos are not available for this room type.

    Apparteo Bordeaux

    STUDIO SUPERIOR

    Room photos

    Photos are not available for this room type.

    Room overview

    Occupancy
    Guests: 1–5 • Adults: max. 5 • Children: max. 3
    Room type
    STUDIO
    View / characteristic
    SUPERIOR

    Adult and child limits apply within the room's total guest limit.

    Room code: STU.SU

    Limited room details from hotel

    Available rooms, prices and included facilities are confirmed after you choose your dates and rate.

  • Room TWO BEDSRoom • TWO BEDSROO.2B

    Photos are not available for this room type.

    Apparteo Bordeaux

    Room TWO BEDS

    Room photos

    Photos are not available for this room type.

    Room overview

    Occupancy
    Guests: 1–10 • Adults: max. 10 • Children: max. 6
    Room type
    Room
    View / characteristic
    TWO BEDS

    Adult and child limits apply within the room's total guest limit.

    Room code: ROO.2B

    Limited room details from hotel

    Available rooms, prices and included facilities are confirmed after you choose your dates and rate.

  • DOUBLE STANDARDDOUBLE • STANDARDDBL.ST-1

    Photos are not available for this room type.

    Apparteo Bordeaux

    DOUBLE STANDARD

    Room photos

    Photos are not available for this room type.

    Room overview

    Occupancy
    Guests: 1–4 • Adults: max. 4 • Children: max. 3
    Room type
    DOUBLE
    View / characteristic
    STANDARD

    Adult and child limits apply within the room's total guest limit.

    Room code: DBL.ST-1

    Limited room details from hotel

    Available rooms, prices and included facilities are confirmed after you choose your dates and rate.

  • STUDIO STANDARDSTUDIO • STANDARDSTU.ST

    Photos are not available for this room type.

    Apparteo Bordeaux

    STUDIO STANDARD

    Room photos

    Photos are not available for this room type.

    Room overview

    Occupancy
    Guests: 1–5 • Adults: max. 5 • Children: max. 3
    Room type
    STUDIO
    View / characteristic
    STANDARD

    Adult and child limits apply within the room's total guest limit.

    Room code: STU.ST

    Limited room details from hotel

    Available rooms, prices and included facilities are confirmed after you choose your dates and rate.

  • Double or Twin STANDARDDouble or Twin • STANDARDDBT.ST

    Photos are not available for this room type.

    Apparteo Bordeaux

    Double or Twin STANDARD

    Room photos

    Photos are not available for this room type.

    Room overview

    Occupancy
    Guests: 1–6 • Adults: max. 6 • Children: max. 3
    Room type
    Double or Twin
    View / characteristic
    STANDARD

    Adult and child limits apply within the room's total guest limit.

    Room code: DBT.ST

    Limited room details from hotel

    Available rooms, prices and included facilities are confirmed after you choose your dates and rate.

  • APARTMENT STANDARDAPARTMENT • STANDARDAPT.ST

    Photos are not available for this room type.

    Apparteo Bordeaux

    APARTMENT STANDARD

    Room photos

    Photos are not available for this room type.

    Room overview

    Occupancy
    Guests: 1–10 • Adults: max. 10 • Children: max. 6
    Room type
    APARTMENT
    View / characteristic
    STANDARD

    Adult and child limits apply within the room's total guest limit.

    Room code: APT.ST

    Limited room details from hotel

    Available rooms, prices and included facilities are confirmed after you choose your dates and rate.

Guest reviews

What other guests saying about Apparteo Bordeaux

7.4
Very good
138 Reviews
Cleanliness
8.0 /10
Service
6.8 /10
Comfort
7.4 /10
Condition
8.0 /10
Location
6.0 /10
Neighborhood
6.6 /10
Value
9.4 /10
Amenities
7.0 /10
50 reviews shown
8/10
Excellent
13 Aug 2023
P A

Comfortable, well equipped studio - good value.

Our second visit to Apparteo Bordeaux and equally enjoyable! The room on the top floor was spacious, clean, well equipped and comfortable with a great terrace for outdoor dining - very relaxing and appreciated as it was 30C+. A lot of renovation of the surrounding area makes for a very pleasant stay with loads of waterside restaurants, the lovely Halles de Bacalan and, of course the Cite du Vin.
Can recommend taking the No. 4 bus from directly across the road to the Château de Pape Clemente for one of the best wine tours in Bordeaux.
Partner
10/10
Exceptional
27 Feb 2023
Ben

Good value for money and exceeded.

Good experience, would use these again if I was staying in Bordeaux again.
Partner
4/10
Poor
10 Jun 2019
Arturo
Imposible to get in. Instructions are not clear.
And the phone number in useless. Not help at all.
8/10
Excellent
12 Sep 2018
Wendy

Great value appartments

Great apartment. Bit strange that there is no reception open outside business hours, but that was detailed at time of booking. I arrived Tues night and didn't see any staff until Monday... A mid week linen replacement would have been good, but otherwise great value, nice apartment. Local area is in the middle of urban regeneration, but wasn't noisy or anything... Just quite obviously not finished yet.
8/10
Excellent
28 Aug 2018
P A

Excellent value near Cite du Vin

Excellent, comfortable, pristine studio on the top floor overlooking the marina. The reception staff were very pleasant and efficient and we really enjoyed our 3-day stay here. The room was surprisingly spacious, the kitchenette was well equipped for all our cooking requirements and there is a Lidl and an Aldi within minutes on foot and a huge new LeClerc also very close. Easy walking to the B tram and the new shopping and entertainment development near the Cite du Vin and along the riverside are easily explored. Particularly liked the casual eateries in Les Halles de Bacalan. As it was very hot during our stay (no a/c but a fan is supplied in the room) we walked up to the Lac by the Congress Centre and found a very pleasant beach area and lots of small (mostly Asian) al fresco eateries under the trees. Would certainly stay here again when in Bordeaux.
Partner
4/10
Poor
26 Jun 2018
Akshay

Go here if you want to stay in your room

Without Air-conditioning, no real cafeteria/restaurants nearby, and no public transportation (nearest is 750m away, good luck lugging your bags), the only thing this place has going for it is, a thoughtfully laid out kitchenette.
10/10
Exceptional
12 Jun 2018
Verified traveler
Clean, modern and comfortable. Room is nice and big with everything u need.
Free gym access - small but added bonus.
Café on 2nd floor is not mentioned on expedia but nice suprise.
Lovely, helpful receptionist.
Fridge in room is noisy as is road outside are the only negatives I found.
8/10
Excellent
06 May 2018
Verified traveler
I came in the evening, so it was quite dark. It is about 10 min walk away from Rue Achard tram station, so that's the convenient part, but it is quite difficult to find the hostel as the signboards isn't very big. The neighborhood is a bit run down, though the hostel itself is quite good, and there's a lot of construction work going on, which made walking a bit difficult. I quite like the room, since it is quite cozy for one person, and generally it is very well equipped. The check in is automated, so it helped me a lot since I only checked in at 10pm. Overall quite a good place if you want somewhere to crash for a few days.
Friends
8/10
Excellent
13 Oct 2017
Jennifer

Good value for the price... Bordeaux is a great!

Great staff, limited hours at the front desk. 10 min walk from tram was a chore. 10 min to nearest grocery too! A little off the main track, industrial area that would have worried me if I was coming in late. Construction noises meant we had to keep window closed. Clean and good value.
Family
6/10
Pleasant
11 Jul 2017
Vix

Very reasonable stay

Positives - accommodation is clean, tidy and modern with all of the amenities you would expect at this price.
- Despite some negatives, I thought we ultimately got very good value for money.

Negatives - Location isn't great in terms of public transport. It's about a 10-15 minute walk from the closest tram stop along dark streets.
- We didn't see a member of staff for our entire stay, due to us arriving after 6pm when we checked in. All keys are kept in the safe for you to collect yourselves and this potential security issue made me a bit nervous.
- There is a definite youth hostel feel to the accommodation, which you should bear in mind when booking.
- It was incredibly hot at night with no air con. We were lucky to have a private balcony, so we could open the doors to let a breeze in, but some studios seemed to share balconies which would make this impossible.
- It was quite noisy. Not so much the other residents, but we could hear a rave/party one night and on the second night there seemed to be some issues going on in nearby streets.
6/10
Pleasant
24 Jul 2026
Sandrine
Emplacement pratique , logement propre et bien agencé. Par contre très bruyant avec bus et voitures qui passent dans la rue.
10/10
Exceptional
21 Jun 2026
ANTHONY
Très bon accueil au niveau de l'hôtel, très bon emplacement, très proche. De bordeaux lac. Avec commodité de commerces et de restaurants. Très bien, desservi. Par les bus. Hôtel très sympathique chambre très agréable et très fonctionnellelle l'accueil est parfait une gentillesse de la part des gens qui travaillent dans l'hôtel vraiment. Incontestable. Je recommande vivement cet apoarthotel. et j'y reviendrai.
Self
8/10
Excellent
05 Jun 2026
Prince Israel
Séjour calme avec une belle vue depuis le balcon sur les bassins à flots.
En ce qui concerne les transports, il ya une ligne de bus qui nous permet d’accéder directement au centre ville à 15 minutes.
Néanmoins la communication avec l’accueil est impossible en dehors des horaires affichés, le numéro d’urgence est injoignable et ne fonctionne pas.
Partner
8/10
Excellent
25 May 2026
guillaume
Suffit pour juste du couchage.
Vu personne
6/10
Pleasant
05 May 2026
Elora
La chambre était bien, bien équipé. Mais problème d'arriver dans l'hôtel, pas de clé, accueil fermé
10/10
Exceptional
15 Apr 2026
Isabelle
Logement hyper accessible, tranquille, très pratique
10/10
Exceptional
20 Dec 2025
Laurent
La chambre était impeccable, le lit un peu petit
6/10
Pleasant
25 Oct 2025
Delphine

Peut mieux faire

Le ménage est à revoir dans les coins, manque de vaisselle. L'ascenseur est resté en panne tout le long de mon séjour donc c'était génial les 6 étages avec toutes les affaires et deux enfants...
Friends_and_family Family
8/10
Excellent
13 Oct 2025
Nathan
La remise des clefs, rapide et autonme.
J'ai apprécie mon séjour, la localisation etait idéale pour mon weekend au parc des expositions.
Self
10/10
Exceptional
09 Sep 2025
Anaïs
Très bien, appartement spacieux et équipé. Propre. Mention pour le grand balcon
Partner
10/10
Exceptional
03 Sep 2025
patrick

Séjour Agréable

Hôtel bien situé à proximité de la ville. Personnel aimable et accueillant. Hôte très sympa
Self
6/10
Pleasant
01 Jul 2025
Lola

Bof

Pour le prix, nous nous attendions à mieux. Vaisselle sale, peu de produit d’hygiène, pas de torchons, peu de vaisselle, pas de meuble pour ranger les vêtements, pas de sacs poubelle….
La salle de sport est vraiment minuscule.
Je ne recommande pas vraiment
Partner
4/10
Poor
29 Nov 2024
Jacob

Katastrofal

Katastrofal check-in. Manglende værelse og nøgler. Defekt dørlås. Ingen personel i receptionen. Svarer ikke på tlf. opkald. Måtte finde et andet hotel første nat, da vi ikke kunne få adgang vores værelse.
Business
10/10
Exceptional
12 Sep 2024
Stéphanie
Grand appartement propre avec magnifique terrasse.
Bien respecter les conditions d'arrivée car il faut respecter des horaires.
Leisure Friends
4/10
Poor
12 Aug 2024
Verified traveler
Sejour satisfaisant, par contre la securité est douteuse aux alentours de l'hôtel. En plein jour, mon véhicule a été vendalisé sur un parking extérieur situé a 30 m de l'hôtel Apparteo.
Self
10/10
Exceptional
29 May 2024
Christophe
Beau logement à proximité immédiate de toute la zone des restaurants près de la base sous-marine.
Leisure Self
4/10
Poor
18 May 2024
véronique

Pas plus d’une nuit surtout

Je déconseille le canapé lit surtout pour le mal de dos
Le canapé grince au moindre mouvement L’emplacement est bien situé
Partner
10/10
Exceptional
01 Feb 2024
Andre
Rien a dire ca s'est bien passé dans l'ensemble
Self
8/10
Excellent
29 Nov 2023
shifeng
位置一般
Business Self
10/10
Exceptional
27 Nov 2023
claude
Appartement tout en longueur,grande sdb,grande terrasse
Cuisine et table petites
Personnel de l'accueil désagréable et peu présente même pendant les horaires affichés.
Business Partner
8/10
Excellent
08 Nov 2023
Manuela
Tb pour un séjour court
Business
2/10
Poor
03 Nov 2023
Pascale
Hôtel fermé et inaccessible. Honteux.
6/10
Pleasant
25 Sep 2023
Kokoro
土日など時間外チェックインは連絡必須とのことですが、事前連絡が取れず、かなり手間がかかり
ました。鍵の受け渡しは前日に連絡がきましたが、上記日程、時間になる場合はお気をつけ下さい。あとエアコンはありませんので暑い時期は考慮して選んだ方がいいと思います。
ただバス停も目の前ですし、便利だと思います。
Leisure Friends
10/10
Exceptional
11 Sep 2023
Marion
Le seul petit point noir c’est le manque de climatisation. Sinon très bon rapport qualité/prix
Leisure Self
6/10
Pleasant
25 Aug 2023
Francisco Javier
Correcto lo único necesita un repaso limpieza .
No está sucio pero si un repaso.
Gracias.
Leisure Self
10/10
Exceptional
08 Aug 2023
Jennifer

Très bien sauf sol et poussière à revoir

Studio très bien avec un grand Balcon. Manque la propreté poussière et sol et lavage de sol bof. SDB très propre. J'ai passé un bon coup de balais en arrivant dans le studio hors SDB. Dommage sinon très bien résidence calme, belle vue sur le port de Bordeaux.
Partner
8/10
Excellent
05 Aug 2023
Alizée
Salle de sport pas toujours ouverte dommage…
Leisure Partner
8/10
Excellent
21 Apr 2023
Marie-Laure

Bien pour son emplacement

Emplacement pratique, assez proche du centre ville mais en restant au calme. Le parking est un plus (pensez à réserver votre place pour en avoir le numéro). Par contre le canapé lit manque de confort et une tablette pour poser ses affaires à côté de la tête de lit serait utile. Pas de climatisation, uniquement un ventilateur. Personnel de l'accueil très agréable.
Business
10/10
Exceptional
02 Apr 2023
Nicolas
excellent rapport qualité prix et tres bien placé.
8/10
Excellent
28 Feb 2023
Mariana sofia

Check in

Chegámos a um sábado e não havia ninguém presente para nos receber. Vimos o papel na porta que há um rapaz que ajuda,. Fomos chamá-lo e ele ajudou nos e explicou tudo. Muito prestável. Deveríamos ter um código para abrir o cofre onde se encontravam as chaves e as informações todas do apartamento e não tínhamos.. falhou essa parte. De resto correu tudo bem
Partner
8/10
Excellent
04 Sep 2022
Gilles

Séjour 48h

Convenable
Partner
8/10
Excellent
17 Sep 2021
kagné
Salle de bain un peu plus propre c'est à dire des rideaux de douche propres
Leisure Friends
4/10
Poor
19 Apr 2021
Verified traveler

Fêtes toute la nuit un cauchemar

Fêtes clandestines dans l’hôtel, impossibilité de joindre une personne de l’hôtel car le week-end il n’y a pas d’accueil. Le numéro d’urgence ne répond pas. La fête a durée jusque 6h du matin non stop ils étaient tellement nombreux que la porte de la sdb vibrait. Literie très inconfortable pour le canapé lit. Je ne recommande pas
Partner
10/10
Exceptional
18 Sep 2020
Verified traveler

efficace

un peu excentré mais tres pratique pour visiter le quartier bordeaux lac et cite du vin
Self
8/10
Excellent
02 Sep 2020
Ferrand
Le séjour à été très bien hormis le lit canapé qui peut déranger le sommeil de certaines personnes. Sinon parfait pour une ou deux nuits.
Partner
10/10
Exceptional
18 Jul 2020
KILLIAN

Très bien

Un super séjour à Bordeaux. Un logement récent et agréable avec terrasse très appréciée dans un quartier plutôt calme et sympathique (en mutation). Le logement est fonctionnel et bien agencé. Rien à redire.
Partner
2/10
Poor
07 Jul 2020
Daniel

Très insatisfait

Un problème de clé à mon arrivée. Réception fermée, 1er numéro appelé sur messagerie, 2ieme numéro \" d'urgence\" on m'indique qu'on me rappelle ... j'attends toujours ... promesse de rappel non tenue ... juste incroyable, je ne me serais pas débrouillé tout seul j'avais loué une nuit sans pouvoir l'utiliser, sans pouvoir renter dans l'appartement. Personnel qui répond au téléphone pas professionnel du tout, et très antipathique, .... à éviter absolument.
Business
4/10
Poor
08 Mar 2020
Patrick

Déçu...

Pas de wifi correct dans la chambre .
Canapé lit pas très confortable ..
Déçu..
Business
8/10
Excellent
08 Jan 2020
Emmanuel
Facilités pour récupérer les clés tardivement, bonnes explications, suivi sérieux. Bon rapport qualité prix.
Business
8/10
Excellent
20 Aug 2019
Verified traveler
Appart'Hotel sympa mais ni plus ni moins, ne pas s'attendre à quelque chose d'extraordinaire niveau propreté c'est juste, rapport qualité prix ça va
Partner

Location & surroundings

Apparteo Bordeaux
30 Cours Henri Brunet, Bordeaux, France

Hotels Nearby

Compare other stays close to this hotel. Choose travel dates to check availability.

Explore the map
Show 46 more nearby hotels

Apparteo Bordeaux

25 hotel photos