At least as long you pay for the service is the answer but probably longer.
Some charge for unlimited storage and some charge by the byte stored, therefore it makes no sense for the unlimited services to delete your old data to save storage space.
In truth, you will eventually have to decide what data you can finally flush and delete it yourself - no one at the backup service is going to take that action.
Some backup services will deleted files after a delay of a certain number of days (usually 30), others may never delete it.
It's easy enough to find out what your provider's policy is by just calling and asking - while you are at it ask, what features your plan offers to address data archiving.
As an aside, online backup services that are offered by large, nationwide vendors with redundant, spread out, and heavily secured storage facilities are a very safe place to put your data. At a minimum, your data is stored across an array of servers.
As these services evolve and grow, your data will likely be stored even across different states.
This diversity of data archiving paints a picture of very secure encrypted data that is randomly placed across multiple servers. Very very hard for a hacker or other evildoer to justify the hours it would take to get at your family reunion pictures.
Those services have every incentive in the world for maintaining, protecting, and asking you before any changes or deletions would be made to anything you indicated you wanted done to your data.
Even some diabolical employee who could get mad at the online company and damage or delete customers' files etc, would require an person have outside computing power to break the super secure 256-bit AES/448-bit Blowfish encryption algorithm that protects your data from the moment it leaves your computer.
Let's face it - It's hard not to be a bit uneasy when your data that you have kept under lock and key is suddenly stored far away. Rest assured your data is ultra safe and with the best services, will be available even if you leave their program.
But the physical security of the major online backup services and their ultra rich encryption is bottom line a lot better than anything you could put together at your home or office.
Roger G. Brown is data backup and security expert. He has significant experience in helping individuals and small businesses make cost-effective decisions about data backup and storage. If you want to learn how to avoid losing your data, check out Roger's website at http://www.onlinebackupstoragereviews.com.
