accounting package

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What accounting software does most software startups use

Quickbooks hands down - been using it for years at multiple start-ups. All CPA firms will have the ability to take a copy of your file and use it to prepare audited financials as well as tax returns.

They have a very robust community here:

http://community.intuit.com/quickbooks

There is also a pretty robust third party app community as well.

http://community.intuit.com/marketplace

Peter. The dominant player in the start-up accounting software market is Quickbooks, and no one else is even close. They achieved this because, as the name implies, it is such a user friendly system. Accounting professionals used to scoff at Quickbooks as not being a very sophisticated system. Beign a CPA, I know; I was one of them. However, their growth has afforded them the ability to increase their products' features and abilities to be on par with many of the high end accounting systems. Now, most CPAS use it for their clients' books.

They now have an online version, which means the software and your data is stored remotely on their servers for a monthly fee, rather than incurring the expense and risk of it on your computer (or server). The online version also affords you the opportunity to quickly set up multiple users with various permission levels anywhere in the world as long as they can get an internet connection. It is CONTINUALLY updated with new features and improvements, rather than having to upgrade your software to the latest version. It works great, and I use it for all of my outsourced accounting clients. I pass along a big discount on the monthly Qb online subscription to all of my clients and charge a small monthly fee to process all of their transactional and reporting work for them. I'd be happy to answer any questions about it.

Wave Accounting is a free online accounting program for small businesses. You don't need any accounting expertise to use it, but it's more than just an expense tracker (i.e., if you use an accountant, s/he can get all the right reports from Wave). Wave has invoicing tools, one-look dashboards, and other tools that save you time.
You can even connect your bank account to Wave (optional) and all your transactions will automatically import, so that you never need to input anything manually.
And in Wave you can manage your personal and business expenses in the same app. That makes it easy to deal with business expenses paid from a personal account (and vice versa).
Would love to have you try it out. Our support team is awesome and happy to help you get set up.
--Rob (from Wave)