Default port for SQL Server

1. The default SQL Server port is 1433 but only if it's a default install. Named instances get a random port number.

2. The browser service runs on port UDP 1434.

3. Reporting services is a web service - so it's port 80, or 443 if it's SSL enabled.

4. Analysis services is 2382 but only if it's a default install. Named instances get a random port number.

If you have access to the server then you can use

select local_tcp_port from sys.dm_exec_connections where local_tcp_port is not null

For full details see port number of SQL Server

The default, unnamed instance always gets port 1433 for TCP. UDP port 1434 is used by the SQL Browser service to allow named instances to be located. In SQL Server 2000 the first instance to be started took this role.

Non-default instances get their own dynamically-allocated port, by default. If necessary, for example to configure a firewall, you can set them explicitly. If you don't want to enable or allow access to SQL Browser, you have to either include the instance's port number in the connection string, or set it up with the Alias tab in cliconfg (SQL Server Client Network Utility) on each client machine.

For more information see SQL Server Browser Service on MSDN.