Try reviewing usage to determine if you are a heavy minutes or a heavy concurrency company.
This is geared towards companies considering service after building their own SIP based VOIP platform as most service providers for smaller companies offer unlimited plans rather than giving a minutes-based option, which can be far cheaper.
Companies looking to reduce telephony costs with a managed VOIP platform should review how they use their systems and service. Many companies pay for minutes they don’t use, or for more lines than they require. When I’ve helped companies analyze all their telephony related invoices, simple changes in service have allowed significant savings. Enough that replacing the old key system with a new VOIP system is paid off in less than 12 months.
Step one is to get a Call Detail Report (CDR) from all of your current phone providers. You need to see toll free and outbound minutes for local, intraLATA (local long distance), and interLATA (long distance). With VOIP, stop thinking local versus long distance and just think total outbound minutes. AND, if you can’t get a CDR from your provider, switch to a provider that will!
Once you have a couple of months of reports, consider two things for outbound calling: (1) count the total outbound minutes and (2) then look for then number of minutes used on each line.
If the minutes are low but each line is used equally, you may be a heavy-concurrency company. Basically, if you have a sales meeting and then each of your 20 employees is on the phone at the same time for an hour, you need to make a lot of calls at the same time (heavy concurrency). There are minutes based plans that allow unlimited concurrency out there.
If on the other hand you have tons of minutes and barely use some of your existing lines, you are a heavy-minutes company. Maybe you have a sales group that is always on the line. In that case cutting lines and/or going with unlimited minutes makes sense (heavy minutes).
Toll free inbound is a different beast. Look at the cost per minute and location from which people call. Cost per minute varies greatly across different providers. If you are barely using the line, your client base may have made a switch cell phones or be local and considerate enough to call direct.
If clients are all calling from the same general area, there is also the option to set up a local number for that group to switch them off the toll free line. An added bonus is they begin to think of you as a local provider.