Rillet does more native indirect tax than most general ledgers. It calculates value added tax (VAT) and goods and services tax (GST) on invoices for the UK, Australia and Canada, and since August 2026 it files the UK HMRC Making Tax Digital (MTD) VAT return end to end. The question for a Rillet user is not whether the enterprise resource planning (ERP) system handles tax. It is which tax tool goes next to it.
Rillet answers most of that itself. Its help pages say US sales tax is not native, and its Canadian tax support page lists the cases where you still need a third-party engine. Rillet’s Tax integration category names eight partners, and this post covers all eight, plus Commenda and Fonoa. Commenda is the pick for teams that need US sales tax and non-UK VAT in one place, Anrok is the runner-up for US-only software as a service (SaaS) sellers, and Zamp is the pick for teams that want the work run as a managed service. Full ranking below.
How does AI tax software for Rillet compare at a glance?
Ten tools cover indirect tax for a Rillet stack. Eight sit in Rillet’s own Tax integration category and connect today. Two do not: Commenda, which connects through its own Rillet integration, and Fonoa, which is here because Rillet publishes no European Union VAT filing at all and Fonoa is built for exactly that. Ratings are current G2 figures, verified September 2026.
| Software | Best for | In Rillet’s Tax category | Rating |
|---|---|---|---|
| Commenda | Rillet users who need US sales tax and non-UK VAT in one platform | No | 4.7/5 |
| Anrok | US-only SaaS sellers billing through Stripe or Chargebee | Yes | 4.5/5 |
| Zamp | Teams that want US sales tax run as a managed service | Yes | 4.7/5 |
| Kintsugi | US calculation through registration and filing, with address validation | Yes | 4.6/5 |
| Sphere | Cross-border sellers wanting sales tax, VAT and GST in one system | Yes | 5.0/5 |
| Avalara | Enterprise US sales tax across a very large jurisdiction set | Yes | 4.0/5 |
| Numeral | Growing ecommerce and SaaS sellers on US sales tax | Yes | 3.8/5 |
| Fonoa | Exposure that sits mostly outside the United States | No | 4.6/5 |
| CereTax | High-volume billing with special districts and telecom levies | Yes | No rating published |
| Taxwire | Hands-off managed US registration and filing | Yes | Rating not verified at time of writing |
What indirect tax does Rillet handle natively in 2026?
Rillet calculates VAT and GST natively for the UK, Australia and Canada, and files the UK VAT return end to end. It does not calculate US sales tax, monitor nexus, register you anywhere, file outside the UK, manage exemption certificates, or determine product taxability. Rillet states each of those limits on its own pages.
| Capability | Rillet’s native coverage | Source |
|---|---|---|
| UK VAT calculation | Standard, reduced, zero-rated, reverse charge and exempt; the UK standard rate is 20% | rillet.com, gov.uk |
| UK VAT filing | End-to-end HMRC Making Tax Digital returns since August 2026, one-click or auto-approved, no extra fee | rillet.com |
| Australia GST | 10% GST plus Business Activity Statement variants | rillet.com |
| Canada GST/HST/PST | Line-level calculation, including GST plus provincial sales tax composites | info.rillet.com |
| VAT reporting | Reports for 7 countries: UK, Australia, Canada, South Africa, Switzerland, Lithuania and India | rillet.com |
| US sales tax | Not native. Runs through an integration such as Avalara or Anrok | rillet.com |
| Nexus monitoring | None. “Nexus” appears zero times in Rillet’s published API spec | rillet.com |
| Registration, non-UK filing, exemption certificates, product taxability | None | info.rillet.com |
Rillet publishes the trigger list itself. You may still need a third-party tax engine for “automated place-of-supply determinations”, “product/service taxability rules”, “high-volume, real-time rate updates across many jurisdictions”, “cross-border and multi-country tax calculations”, or “evidence management (for example, exemption certificates)” (info.rillet.com).
There is no European Union VAT filing either. No member-state returns, no One Stop Shop (OSS), no Import One Stop Shop (IOSS). If you sell digital services into the EU, the OSS scheme is handled outside Rillet.
Which is the best AI tax software for Rillet in 2026?
Commenda is the best fit for most Rillet users. Rillet already files UK VAT, so the real gap is US sales tax plus everything outside the UK. Commenda covers registration, filing and remittance across 70+ countries and all 50 US states in one platform, which matches that gap. The eight Rillet partners below, and Fonoa, each cover a narrower slice.
1. Commenda
Commenda is a global indirect tax platform covering VAT, GST and sales tax in 70+ countries. For a Rillet user it handles what Rillet leaves out: US sales tax end to end, plus filing everywhere Rillet reports but does not file. Commenda is not in Rillet’s Tax integration list. It connects through Commenda’s own Rillet integration, which reads your invoice and revenue data out of the ledger.
Strengths:
- Monitors economic and physical nexus in all 50 US states, EU member states and 70+ countries against the post-Wayfair thresholds of $100,000 in sales or 200 transactions that apply in most states (Commenda US nexus guide)
- Registers and files US sales tax permits in all 50 states, EU VAT including OSS and IOSS, and GST in Australia, Canada, Singapore and New Zealand (commenda.io/indirect-tax)
- Manages exemption certificates and product taxability, two of the five cases Rillet names for a third-party engine
- 100+ integrations including Stripe, Chargebee, NetSuite and Sage Intacct (commenda.io/integrations)
- Typically replaces 3 to 5 vendor relationships, with roughly 30 days to operational (commenda.io)
Weaknesses:
- A US-only seller with a single sales channel and no international plans may be adequately served by a narrower point solution
Best for: Rillet users who owe US sales tax and also file VAT or GST outside the UK.
Rating: 4.7/5 on G2.
2. Anrok
Anrok is a US sales tax platform built for SaaS companies. On Rillet it calculates tax on every invoice, whether that invoice comes from a closed-won CRM deal or is created by hand, and keeps credit memos, refunds and cancellations in sync (rillet.com).
Strengths:
- Applies sales tax automatically to every Rillet invoice, including invoices generated from CRM deals (rillet.com)
- Forecasts estimated tax on future invoices, so remittance obligations appear before the cash does (rillet.com)
- Integrates deeply with modern billing tools such as Stripe and Chargebee (rillet.com)
Weaknesses:
- US sales tax only, and built for SaaS. Rillet’s own write-up says international expansion “means adding more tools and complexity” (rillet.com)
Best for: US-only SaaS sellers on Rillet with modern billing.
Rating: 4.5/5 on G2.
3. Zamp
Zamp is a managed US sales tax service rather than self-serve software. Specialists own calculations, registrations, filings and state notices, and results flow into Rillet with citations and audit history attached (rillet.com). You approve, they do the work.
Strengths:
- Tax specialists map a tax code to every product you sell, backed by an in-house taxability library, with state guidance and citations attached (rillet.com)
- Covers nexus tracking, registrations, calculations, filings, remittance and notice management as one service (rillet.com)
Weaknesses:
- Scope is US sales tax. A Rillet user selling into Europe still needs a second tool
Best for: Rillet teams that do not want anyone in-house becoming a sales tax specialist.
Rating: 4.7/5 on G2.
4. Kintsugi
Kintsugi covers the full compliance cycle from product taxability through registration and filing. Customer, product and invoice data flows from Rillet into Kintsugi automatically, so your exposure position stays current instead of being rebuilt at quarter end (rillet.com).
Strengths:
- Maintains rule changes across 12,000+ US jurisdictions and 100+ countries, with expert review applied to calculations (rillet.com)
- Handles registrations, state portals, filing deadlines, reconciliation and voluntary disclosure agreements for back taxes (rillet.com)
- Validates product tax categories and addresses before tax is calculated (rillet.com)
Weaknesses:
- G2 reviewers report integration problems with certain payment systems (g2.com)
Best for: Rillet users who want US calculation, registration and filing from one vendor.
Rating: 4.6/5 on G2.
5. Sphere
Sphere handles sales tax, VAT and GST in one system rather than splitting countries across tools. Rillet’s own tax software round-up names it the pick for global SaaS and cross-border compliance (rillet.com).
Strengths:
- One system for US sales tax and international VAT and GST, with no third-party network behind it (rillet.com)
- Continuously indexes global tax law, so a question like whether a SaaS product is taxable in Singapore is answered without research (rillet.com)
Weaknesses:
- G2 reviewers flag a complex interface (g2.com)
Best for: Rillet users selling across borders who want one indirect tax vendor.
Rating: 5.0/5 on G2.
6. Avalara
Avalara is the legacy US sales tax engine, and the first one Rillet names when it describes how US sales tax runs. The integration sends every invoice and credit memo for real-time calculation, then commits them for filing on your schedule (rillet.com).
Strengths:
- Tax content covering 12,000+ US jurisdictions and 200+ countries (rillet.com)
- Edit and recalculate an invoice after it is sent, then batch commit, instead of voiding and reissuing (rillet.com)
Weaknesses:
- Aimed at large enterprises. Rillet’s write-up says it suits teams with “a robust budget for software and tax advisors” and dedicated tax staff (rillet.com)
Best for: Larger Rillet users with complex multi-entity US tax and a tax team to run it.
Rating: 4.0/5 on G2.
7. Numeral
Numeral is a US sales tax automation tool for growing ecommerce and SaaS sellers, covering registration, reporting and filing. The Rillet integration is the standard connector: connect, choose a sync-from date, enable document recording (rillet.com).
Strengths:
- Draws tax content from 12,000+ US jurisdictions and over 200 countries (rillet.com)
- Shows estimated tax on scheduled invoices for forward visibility (rillet.com)
Weaknesses:
- The lowest verified rating here at 3.8/5 on G2, where reviewers report filing delays and unresolved account issues (g2.com)
Best for: Growing US sellers on Rillet who want to keep tax knowledge in-house.
Rating: 3.8/5 on G2.
8. Fonoa
Fonoa is an application programming interface (API) first indirect tax platform for cross-border digital businesses. It is on this list for one reason: Rillet files no European Union VAT return, and Fonoa covers the ground Rillet’s native VAT stops short of. Rillet does not list it, so it connects through Fonoa’s own API rather than a native connector.
Strengths:
- Validates tax identification numbers across 120+ countries in real time (fonoa.com)
- Prepares and submits returns directly to tax authority portals, and is recognised by HMRC for Making Tax Digital (fonoa.com)
- Covers electronic invoicing across 150+ countries, which matters as EU mandates come into force (fonoa.com)
Weaknesses:
- No native Rillet integration, so connecting it is engineering work rather than a setup step
- Registration does not appear anywhere in its published material, so you would still register elsewhere
- Its own pages give different coverage figures for the same scope, so check which number applies to your markets before you buy
Best for: Rillet users whose exposure is mostly international, especially inside the EU.
Rating: 4.6/5 on G2.
9. CereTax
CereTax is a sales tax and VAT calculation engine built for high-volume, complex billing. Connected to Rillet it calculates the moment an invoice is created and writes the jurisdiction breakdown back, so each invoice carries the detail rather than a single tax line (rillet.com).
Strengths:
- Rooftop-level address validation before calculation, so the rate reflects where the sale happened (rillet.com)
- Built for special districts, telecom levies and utility surcharges (rillet.com)
- Records an invoice as a quote and posts it for compliance when it is marked paid, so nothing is committed by hand at month end (rillet.com)
Weaknesses:
- Rillet notes the configurability “requires significant setup and technical resources” (rillet.com)
Best for: Rillet users with usage-based or telecom-style billing and engineers to configure it.
Rating: CereTax has a G2 profile but no rating published.
10. Taxwire
Taxwire is a managed US filing service with its own calculation engine. It calculates tax on every Rillet invoice, watches where you approach a new obligation, and files the returns (rillet.com).
Strengths:
- Files returns and manages notices and remittances across every jurisdiction where you have an obligation (rillet.com)
- Flags where you have nexus and where you are approaching a state threshold (rillet.com)
- Stores, validates and monitors exemption certificates (rillet.com)
Weaknesses:
- Rillet describes the managed model as “maximum convenience with minimum control” (rillet.com)
Best for: Small Rillet teams that want US filing entirely off their plate.
Rating: Rating not verified at time of writing.
How do you choose AI tax software for a Rillet business?
Start from what Rillet already does. If you only sell in the UK, Rillet’s MTD filing may be enough on its own. If you sell into the US, you need a sales tax engine, because Rillet has none. If you sell into the EU or beyond, you need a tool that files where Rillet only reports. Then decide between software you run and a service someone else runs.
Do you need US sales tax, non-UK VAT, or both?
Both is the common answer, since Rillet’s buyer is a scaling SaaS company. A US-only need points to Anrok, Zamp, Kintsugi or Numeral. A both-sides need points to Commenda or Sphere, because splitting US and international across two vendors means two integrations and two audit trails. If your exposure is almost entirely outside the US, Fonoa is worth a look for its electronic invoicing coverage, though you would register elsewhere. The difference between VAT and sales tax drives most of this choice.
Do you want software or a managed service?
Zamp and Taxwire run the work for you. Avalara, CereTax, Numeral and Sphere are engines you configure. Commenda and Kintsugi sit in between, with the platform doing the monitoring and filing while your team approves. Check the current US nexus thresholds before you scope any of it.
Are you already filing UK VAT through Rillet?
Keep it there. Rillet’s MTD filing costs nothing extra and the journal entries are already correct. Buy a tax tool for what Rillet does not file, not to replace a UK return you have working. Rillet’s own tax software round-up recommends seven third-party vendors and no Rillet-native option, which tells you how Rillet sees the split.
When does Commenda make sense for Rillet?
Commenda makes sense when your obligations cross a border Rillet does not file across. Commenda’s global indirect tax platform monitors nexus in all 50 US states and 70+ countries, registers you where you cross a threshold, files the returns, and manages exemption certificates and product taxability. Rillet stays the ledger. Commenda handles the calculation, the registration and the filing.
That matters most when a company outgrows one market, the stage Rillet’s buyer is usually at. Use the sales tax calculator for a rate lookup and the US nexus guide for exposure. The calculator returns rates. It does not tell you where you have crossed a threshold.
How does Commenda work with Rillet?
Our Rillet page shows how Commenda reads invoice and revenue data out of Rillet and handles sales tax and global VAT on top of it, and what stays in Rillet.
Read sales tax and global VAT software for Rillet.
Book a demo to get a free nexus exposure assessment across every state and country your Rillet data touches.
