What aircraft does SQ121 use?

Singapore Airlines flight SQ121 operates on a Airbus A350-900 from KUL to SIN.

How long is the SQ121 flight?

The estimated flight time for SQ121 from KUL to SIN is approximately 0h 52m covering 297 km (185 miles).

How many seats does this Airbus A350-900 have?

This Singapore Airlines Airbus A350-900 has 303 total seats across 2 cabin classes: Business, Economy.

What cabin classes are available on this aircraft?

This Airbus A350-900 offers 2 cabin classes: Business, Economy. Seat distribution: 40 Business seats, 263 Economy seats.

What route does SQ121 fly?

Singapore Airlines flight SQ121 operates from KUL (Kuala Lumpur International Airport) to SIN (Singapore Changi Airport), connecting Sepang and Singapore.

How do I choose the best seat?

The best seat depends on your priorities. For extra legroom, choose seats near emergency exits or bulkhead rows. For quick boarding/deplaning, select seats near the front. Avoid seats near lavatories or galleys if you prefer a quieter flight. Window seats offer views and a wall to lean against, while aisle seats provide easier access to move around.

What do the different seat colors mean?

Green seats are typically available for selection, red seats are occupied or blocked, yellow/orange seats may have restrictions or extra fees, and blue seats often indicate premium or preferred seating with additional charges. Hover over any seat to see specific details and pricing.

Can I change my seat after booking?

Yes, most airlines allow seat changes after booking, though fees may apply depending on your fare type and desired seat. You can typically change seats through the airline's website, mobile app, or by calling customer service. Some seats become available closer to departure as the airline releases blocked inventory.

When is the best time to select seats?

The best time varies by strategy. Book immediately after purchasing your ticket for the widest selection, or wait until 24 hours before departure when airlines often release blocked premium seats. For popular routes, early selection is recommended. Our seat alerts can notify you when preferred seats become available.

Are the seat maps updated in real-time?

Our flight seat maps are updated regularly throughout the day to reflect current availability. However, seat availability can change rapidly, especially close to departure. We recommend checking the airline's official website for the most up-to-date information when making your final selection.

What if my preferred seat isn't available?

You can also check back periodically as seats often open up closer to departure when other passengers make changes or when the airline releases additional inventory.

SQ121 Seat Map

● On time

Singapore Airlines · Airbus A350-900 · Wed, 22 Oct 2025

Depart

KUL · Sepang

0h 52m

185 mi

Arrive

SIN · Singapore

+ Seat alert

J · Business

26/40

Y · Economy

164/263

Filter:

First Business Premium Economy Economy Extra legroom / exit Occupied Blocked

View:

Business · Economy · Rows 11–70

100%

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Get seat alerts

Top picks · Economy

Highest-scoring available seats on this aircraft

46G

Score 68 #1

Easy aisle access · Near wings (smoother ride)

Aisle

46D

Score 68 #2

Easy aisle access · Near wings (smoother ride)

Aisle

46C

Score 68 #3

Easy aisle access · Near wings (smoother ride)

Aisle

52K

Score 68 #4

Window view · Near wings (smoother ride)

Window

Get Seat Alerts

SQ121 Flight Details

Flight Number: SQ121

Origin:

(Kuala Lumpur International Airport, Sepang)

Destination:

(Singapore Changi Airport, Singapore)

Distance: 297 km (185 mi)

Est. Duration: 0h 52m

Flight Date: October 22, 2025

Aircraft: Airbus A350-900

Airline Routes: View Singapore Airlines route map

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Flight Route Map

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Aircraft Configuration

Aircraft Details

Seating info & configuration

Airline: Singapore Airlines (SQ)
Aircraft: Airbus A350-900
Seating: Main Deck: 303 seats

Economy: 263

164 78 21

62% Available

Business: 40

26 6 8

65% Available
Legend: Seat Status

Blocked

Occupied

Standard

Cabin Classes

First

Business

Premium Economy

Economy

Extra legroom / exit

Features

Exit door

WC Lavatory

GALLEY Galley

CREW Crew area

This Airbus A350-900 operates Singapore Airlines flight SQ121 from Sepang (KUL) to Singapore (SIN). Browse the interactive seat map above to find the best seats for your journey, view real passenger reviews, and explore detailed cabin configurations to make an informed decision for your flight.

Best Seats on SQ121

Based on legroom, location, and passenger preferences

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Best Window Seats

Seat 52K Economy
Seat 50K Economy
Seat 50A Economy

Best Aisle Seats

Seat 46G Economy
Seat 46D Economy
Seat 46C Economy

Quietest Seats

Seat 47D Economy
Seat 47A Economy
Seat 46K Economy

Recommendations based on seat characteristics, cabin position, and proximity to facilities. Availability may vary by date.

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Seat Selection Assistance

Seat Alerts Require Payment

Seat alerts are available to users with a paid plan or credits. This feature monitors seat availability and notifies you when your preferred seats become available.

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