Not sure where you owe sales tax? Start with the free Nexus Checker.

ECOMMERCE SALES TAX COMPLIANCE

More selling channels. One managed compliance process.

Selling through your own store, online marketplaces, and multiple states creates more than a tax-calculation problem. IST helps manage nexus, registrations, filings, notices, and sales tax exposure as your ecommerce business grows.

Check Your Nexus Risk →

Or talk to an IST specialist about your current channels and registrations.

YOUR SELLING FOOTPRINT

Every channel affects the compliance picture.

01   Your online store

Direct sales may require seller collection when state obligations apply.

02   Marketplaces

Facilitator collection can help, but does not resolve every seller obligation.

03   Inventory & locations

Warehouses, fulfillment stock, and physical presence can change your nexus footprint.

IST reviews the full picture, not one channel in isolation.

WHO THIS IS FOR

Built for sellers whose tax footprint keeps changing.

DTC & online stores

Grow beyond your home state without losing sight of registration and filing obligations.

Marketplace sellers

Understand what marketplaces collect and what remains your responsibility.

Multi-channel brands

Bring marketplace, storefront, and accounting records into one compliance review.

WHY ECOMMERCE GETS COMPLEX

A collected tax is not the same as completed compliance.

A marketplace might collect tax for a transaction, while the seller still needs to track nexus, maintain registrations, reconcile sales, or file returns where required. Rules and reporting requirements vary by jurisdiction.

And a direct-to-consumer channel may create responsibilities that marketplace collection never covers.

Marketplace vs. direct sales

Separate marketplace-facilitated transactions from sales where your business is responsible for collection.

Economic and physical nexus

Review state sales activity alongside inventory, warehouses, staff, and other physical-presence factors.

Product taxability and exemptions

Identify where product categories, resale certificates, and exempt transactions need attention.

State returns and notices

Manage the filing and state correspondence work that continues after tax is calculated.

MANAGED ECOMMERCE COMPLIANCE

The work IST handles beyond checkout.

The right workflow depends on where you sell, which states require action, and the quality of your transaction records.

01

Nexus analysis

Review sales activity, physical presence, and marketplace factors to identify possible obligations.

02

State registrations

Coordinate appropriate permits and registration steps when collection obligations begin.

03

Returns & remittance

Organize filing schedules, prepare returns, and manage the recurring remittance workflow.

04

Marketplace reconciliation

Review seller and marketplace transaction data to support appropriate state reporting.

05

Notices & exposure

Respond to state correspondence and assess older periods that may need cleanup.

06

Data & AutoFill

Use reviewed transaction and document information to support the managed compliance process.

TWO CHANNELS. DIFFERENT RESPONSIBILITIES.

The marketplace collects. Who handles the rest?

Marketplace orders

A facilitator may collect and remit tax on covered marketplace sales. Sellers can still have nexus, registration, documentation, or reporting responsibilities depending on the state.

Review: platform-collected tax, sales reports, inventory locations, and state treatment.

Your own storefront

Direct sales generally remain the seller’s collection responsibility once applicable nexus and taxability requirements are met. Registration and filing work also needs ownership.

Review: taxable sales, nexus thresholds, registrations, exemptions, and returns.

HOW IST WORKS WITH YOUR TEAM

From scattered sales data to a managed process.

01

Map channels

Identify storefronts, marketplaces, states, and fulfillment locations.

02

Review obligations

Assess nexus, registrations, taxability issues, and historical gaps.

03

Build the filing workflow

Align transaction data, filing calendars, review steps, and state reporting.

04

Manage & adjust

Handle recurring filings and notices as sales channels and states change.

TECHNOLOGY + SPECIALIST OVERSIGHT

Connected data is useful. Owned compliance is better.

IST supports Salesforce and API-connected workflows, as well as ecommerce, ERP, and accounting data processes. Integration scope depends on your systems and implementation requirements.

IST AutoFill can be configured to prepare tax-relevant document information for human review, helping reduce repetitive entry without replacing professional judgment.

Discuss Your Data Workflow →

PRACTICAL DATA CHECKLIST

Sales by state

Transaction dates, destinations, amounts, and seller channel.

Marketplace reports

Platform-facilitated collections and seller proceeds.

Product & customer details

Taxability inputs and exemption documentation when relevant.

Registration & filing history

Active permits, filing frequencies, prior submissions, and notices.

ALREADY SELLING ACROSS STATES?

Past exposure needs a plan, not a guess.

If sales, marketplace activity, or inventory created obligations before registration, IST can review prior periods, estimate exposure, and evaluate options such as registrations or voluntary disclosure where available.

Start with clarity.

Understand where your business may have nexus before changing your tax setup.

Free Nexus Checker →

ECOMMERCE SALES TAX FAQ

Questions online sellers ask.

Does Amazon or another marketplace handle all my sales tax?

Not necessarily. Marketplace facilitator rules often require covered platforms to collect and remit tax on marketplace transactions. Your own sales, nexus footprint, registration status, and some reporting obligations may still need attention.

Does storing inventory in another state create nexus?

Inventory held in a state can create physical nexus, including through third-party fulfillment. The result depends on the state and your facts, so the locations need to be reviewed.

Do marketplace sales count toward economic nexus thresholds?

States do not all count transactions the same way. Some include marketplace sales when evaluating thresholds and others use different rules. Review each relevant state rather than assuming marketplace sales do not count.

Can IST help if we missed registrations or filings?

IST offers past-exposure remediation support, including reviewing historical activity, prioritizing states, and considering appropriate registration or disclosure routes.

Will IST replace our store or tax software?

The goal is to manage the compliance work around your existing systems. Any integration, data mapping, or calculation configuration is scoped to the business rather than promised as a universal plug-and-play connection.

READY TO GET CONTROL OF ECOMMERCE SALES TAX?

Your next state should not mean another internal tax project.

Start with a free nexus check or speak with IST about registrations, filings, marketplace reporting, and cleanup.

Check Nexus Risk →

Prefer a conversation? Contact IST →