Covered entities are required to provide aids and services unless doing so would result in an “undue burden,” which is defined as significant difficulty or expense. If a particular aid or service would result in an undue burden, the entity must provide another effective aid or service, if possible, that would not result in an undue burden. Determining what constitutes an undue burden will vary from entity to entity and sometimes from one year to the next. The impact of changing economic conditions on the resources available to an entity may also be taken into consideration in making this determination.
If you do get sued, if you immediately remediate your website, you may be able to get the lawsuit dismissed on mootness (there’s no longer anything in dispute, i.e. plaintiffs are arguing your website is inaccessible but you’ve already made it accessible). This definitely does not mean you should wait to fix your website but it does mean you may have an out.
For most businesses, the need for ADA web compliance means they will need to make at least some adjustments to all of their online marketing strategies. For instance, if your company provides tax preparation services, all of the tax forms you provide for customers to download would need to meet accessibility standards. Any online tax preparation services that you offer would also need to be configured so they meet ADA standards, as would your mobile app.