When expanding your business internationally, it is important to work with both legal and tax experts to avoid potentially costly mistakes and additional expenses in the future. Before embarking on any business, you should consult with local professionals, such as CPAs and attorneys.

In the United States, the equivalent of a value-added tax or GST is the sales tax, which is levied by state and local governments. Forty-six states, the District of Columbia, and many local jurisdictions levy sales and use taxes. Each jurisdiction has different rules, usually in the range of five to eight percent.

In general, sales tax is a tax imposed on the sale or purchase of certain goods and services. Whether a seller is liable for sales tax usually depends on whether there is a temporary or permanent "physical" presence in the taxing jurisdiction, such as an office, inventory or employees. In addition to "physical" presence, there is a broader concept of "economic nexus" that is also used in many states to define sales tax liability and compliance.

Once an economic relationship has been established, a business needs to decide whether it should pay sales tax on the goods or services being sold.

A number of state governments have joined together to create a streamlined sales and use tax agreement designed to simplify sales and use tax administration within member states to substantially reduce the burden of tax compliance, thereby encouraging vendors who do not have a physical presence in the state to voluntarily register and begin collecting taxes on their behalf. Member states hope that Congress will eventually give them the authority to force vendors to collect and pay tax on sales made by mail order, telephone and Internet to clients in states where the vendor does not have a tax nexus.

Those businesses that are required to collect and pay sales tax (or pay use tax) do so by filing a separate sales tax return, which typically may be audited by state authorities within three years. If a business does not file a sales tax return, there is no statute of limitations on audits and collections made for past due taxes.