Area code 991 phone prefixes
This is not a single phone number detail page. It groups prefix ranges linked to area code 991 and points users to the relevant prefix detail pages.
Singapore
How to use this list
This page groups active phone prefixes by country and line type. It helps users understand the expected number format before opening a specific prefix or checking a complete number.
Choose a prefix from the list, then complete the remaining digits on the prefix detail page to search, report or review a full phone number.
A prefix alone is not proof that a call is safe or unsafe. If a caller asks for money, passwords, card details or urgent verification, check the complete number before taking action.
Prefix list FAQ
What does this list show?
It shows active prefixes for the selected country and line type, with example ranges and links to prefix detail pages.
Why are some prefixes less detailed?
Some ranges have no community comments yet. Technical prefix, type and format information still help users check a full number correctly.
How do I check a full number?
Open a prefix detail page or use the site search, then enter the complete phone number for comments, complaints and risk signals.
Area code intelligence
Use this section to see line types, expected number format and how to verify a full number without running extra live queries.
Which line types use this code?
These labels are calculated from the active prefix ranges already loaded for this area code.
Number format
Use the national example with the country calling code to avoid mixing this area code with another country.
- Example
- 99100000
- Country code
- +65 99100000
- Pattern
- #### ####
How to check a full number
Enter the remaining digits on the search page or open a prefix range to review comments, complaints and risk signals.
More phone intelligence for this country
Continue with country-level data for Singapore: reports, spam trends, search activity and prefix statistics.