@JustMe1909 wrote:
I did not claim any depreciation on my rental properties purchased in 2014, 2015, 2016 and 2017. My returns were filed online through turbo tax. Can I amend my returns online using turbo tax going back to tax year 2014 and submit the amendment online through turbo tax to the IRS?
Not only can you not amend online, you simply cannot amend, period. Rather, you must file Form 3115 (and make an adjustment) since, by not deducting any depreciation, you used an impermissible method of accounting.
Unfortunately, preparing Form 3115 is not really a DIY-type endeavor; you will probably need professional tax preparation, or at least guidance from a professional. Regardless, you should rectify this situation as soon as practicable.
See https://www.irs.gov/instructions/i3115#idm140516453720416
