Comply vs Tax Rex ‑ Sales Tax Automationfor Shopify (2026)
Comply and Tax Rex ‑ Sales Tax Automation address vastly different needs within the 'Finances' and 'Taxes' categories on Shopify. Comply is specifically designed for merchants operating point-of-sale systems in Spain, focusing on compliance with Spanish fiscal regulations like Verifactu and (upcoming) TicketBAI. Its strength lies in automating invoice generation, QR code creation, digital signatures, and real-time data submission to Hacienda. In contrast, Tax Rex ‑ Sales Tax Automation targets US-based e-commerce businesses, offering automated sales tax return reports and filing, economic nexus alerts, and simplified state registration. It aims to alleviate the complexities of US state sales tax compliance, enabling businesses to focus on growth rather than tax headaches. The key differentiator is their geographical and regulatory focus. Comply is laser-focused on Spanish fiscal obligations, while Tax Rex ‑ Sales Tax Automation caters to the intricacies of US state sales tax. This difference is reflected in their features: Comply provides tools for generating fiscally compliant invoices and secure data transfer to Hacienda, while Tax Rex ‑ Sales Tax Automation offers features like economic nexus dashboards and automated filing. The stark difference in user ratings and number of reviews (Comply: 0/5, 0 reviews vs. Tax Rex: 5/5, 91 reviews) suggests a substantial difference in the user base and potentially in the maturity of the apps.
At a Glance
Comply
0 reviews
Tax Rex ‑ Sales Tax Automation
91 reviews
Detailed Overview
Comply
Con Comply, tu punto de venta opera conforme a las obligaciones fiscales vigentes en España.
Key Features
- Facturas con QR y firma digital: Documentos válidos según normativa fiscal.
- Envío seguro de datos a Hacienda: Cumple con Verifactu y TicketBAI(próximamente)
- Gestión de errores: Detecta y corrige facturas rechazadas o envíos incompletos.
- Panel fiscal Shopify: Visualiza, filtra y exporta todas tus facturas facilmente.
Tax Rex ‑ Sales Tax Automation
US State Sales Tax return Reports & Automated Filing for your store. Easy, Accurate & Time Saving!!!
Key Features
- Timely Autofile: Ensure on-time tax return filings while you focus on business
- Accurate Tax Reports: Precise sales tax reports tailored to state's requirements
- Economic Nexus Alerts: Stay informed on new state nexus thresholds
- Effortless State Registration: Simplified new state registration for compliance
- Ability to Ignore orders imported from Marketplaces like Amazon, Ebay, etc
Feature Comparison
| Rating | 0/5 | 5/5 |
Rating Comply0/5 Tax Rex ‑ Sales Tax Automation5/5 | ||
| Reviews | 0 | 91 |
Reviews Comply0 Tax Rex ‑ Sales Tax Automation91 | ||
| Geographic Focus | Spain | USA |
Geographic Focus ComplySpain Tax Rex ‑ Sales Tax AutomationUSA | ||
| Regulatory Focus | Spanish fiscal regulations (Verifactu, TicketBAI, SII) | US State Sales Tax |
Regulatory Focus ComplySpanish fiscal regulations (Verifactu, TicketBAI, SII) Tax Rex ‑ Sales Tax AutomationUS State Sales Tax | ||
| Key Feature: Reporting | Panel fiscal Shopify (visualize, filter, export invoices) | Accurate Tax Reports tailored to state's requirements |
Key Feature: Reporting ComplyPanel fiscal Shopify (visualize, filter, export invoices) Tax Rex ‑ Sales Tax AutomationAccurate Tax Reports tailored to state's requirements | ||
| Key Feature: Automation | Automatiza la generación de facturas, códigos QR, firmas digitales encadenadas y el envío en tiempo real a Hacienda | Timely Autofile (ensure on-time tax return filings) |
Key Feature: Automation ComplyAutomatiza la generación de facturas, códigos QR, firmas digitales encadenadas y el envío en tiempo real a Hacienda Tax Rex ‑ Sales Tax AutomationTimely Autofile (ensure on-time tax return filings) | ||
| Target Merchant | Spanish merchants using Shopify POS | US e-commerce businesses |
Target Merchant ComplySpanish merchants using Shopify POS Tax Rex ‑ Sales Tax AutomationUS e-commerce businesses | ||
| Value Proposition | Ensures compliance with Spanish fiscal obligations | Simplifies US state sales tax compliance |
Value Proposition ComplyEnsures compliance with Spanish fiscal obligations Tax Rex ‑ Sales Tax AutomationSimplifies US state sales tax compliance | ||
- Conversion Audit
- Speed Audit
- SEO Audit
Conversion Audit
Our Verdict
The choice between Comply and Tax Rex ‑ Sales Tax Automation is straightforward: it depends entirely on your business location and tax obligations. If you're a merchant operating a Shopify POS system in Spain, Comply is the only viable option, as it directly addresses Spanish fiscal regulations. However, the lack of reviews raises concerns about its reliability and support. If you're a US-based e-commerce business grappling with the complexities of state sales tax, Tax Rex ‑ Sales Tax Automation is the clear winner, offering automated reporting and filing. Its high rating and numerous reviews suggest a reliable and user-friendly solution.
Given the information available, it's difficult to recommend Comply unless you're explicitly required to comply with Spanish fiscal regulations and willing to take the risk of using an unreviewed app. Tax Rex ‑ Sales Tax Automation is the better choice for US-based businesses seeking to automate and simplify sales tax compliance.
Common Questions
Which app is easier to use?
Without user reviews for Comply, it's impossible to definitively say. However, Tax Rex ‑ Sales Tax Automation's positive rating and numerous reviews suggest a user-friendly interface and helpful customer support.
Which app is more expensive?
Pricing information is not provided for either app, so a comparison is impossible.
Which app handles international taxes?
Tax Rex ‑ Sales Tax Automation focuses specifically on US state sales tax. Comply handles Spanish fiscal obligations. Neither appears to address general international taxes.
What happens if Tax laws change?
Both apps aim to stay updated with tax law changes within their respective regions. It is important to confirm that they keep up with the law changes periodically.
Which app can handle offline transactions?
Comply specifically mentions an offline queue, allowing it to handle transactions even without an internet connection. Tax Rex ‑ Sales Tax Automation doesn't mention offline capabilities.
Get More From Your Shopify Store
Run audits for SEO, CRO, PageSpeed, and AI visibility. Get a clear report and actionable fixes.
Try Fix My Store