Get in touch
Questions about cross-border selling, integrations, or logistics? Reach us by phone, email, or the form below — our team typically responds within hours.
- Response
- < 24h
- Languages
- EN & LT
- Support
- Free
- Countries served
- 30+
- Commissions
- Zero
- Setup time
- Guided
- Product sync
- Real-time
Reach us directly
Whether you need technical help, want to discuss a partnership, or just have a question — we are here for you.
Headquarters
Europos pr. 34-47Kaunas, Lithuania
UAB "Mastersel" 307424990
Located in the heart of Europe for optimal cross-border logistics routing.
How it worksEmail Support
For API integration inquiries, logistics tracking, and general support.
[email protected]We typically respond within a few hours during business days.
Phone
Prefer to talk? Call us directly for immediate assistance with your account or integration.
+370 664 80225Available Monday — Friday, 9:00 — 18:00 EET.
How can we help?
Browse common support areas or contact us with your specific question.
Store Integration
Connect WordPress, Shopify, PrestaShop, OpenCart, or custom XML feeds.
Learn moreShipping & Logistics
Courier routing, label generation, and delivery tracking support.
Learn moreCustoms & Compliance
Automated duties, HS codes, and cross-border regulations.
Learn moreReturns
Cross-border return processing and reverse logistics.
Learn moreInventory & Orders
Real-time stock sync, order management, and fulfillment.
Learn morePricing & Billing
Multi-currency pricing, commission-free model, and label zerp costs.
Learn moreFrequently asked questions
How do I integrate my e-commerce store?
Create your account, review the partnership agreement and connect your store. Setup and publication times depend on your platform, product information and marketplace review.
Who handles international returns?
Mastersel handles the entire reverse logistics process. If a customer in another country returns an item, we process the local return, consolidate shipments, and route the inventory back to your warehouse efficiently.
Is the service truly free with zero commissions?
You keep 100% of your listed base price. Mastersel earns revenue by adding our own competitive markup to the final retail price, which we also use to cover all shipping and localization costs.
How are customs and VAT handled?
Our automated logistics engine pre-clears customs and manages VAT compliance for cross-border shipments, ensuring your packages never get delayed at international borders and buyers never face unexpected fees. You don’t need to handle international tax payments, as Mastersel acts as the sole purchaser, reflected in your sales invoices.
What is the typical response time?
We aim to respond to all inquiries within 24 hours on business days. Most requests are answered within a few hours during European business hours.
How does onboarding work?
Installation is completely self-service. Install the Mastersel plugin for your platform, and your products will sync automatically. No calls or meetings required. Start selling now.
Can I migrate from another platform?
Yes. If you are switching from another platform, our plugins ensure a smooth transition. Your product catalog is imported and synced from your existing e-commerce store — no manual data entry required.
Which languages do you support?
Our support team communicates in English and Lithuanian. Product listings are automatically localized into the relevant languages for each target market.
Why responsive support matters
Running a cross-border e-commerce operation means dealing with multiple currencies, languages, tax regimes, and logistics networks simultaneously. When something goes wrong — a customs delay, an inventory mismatch, a courier routing issue — you need answers fast.
Support that understands e-commerce
Our team knows the difference between an HS code and a VAT IOSS number. Whether you are troubleshooting your store integration, checking on inventory sync status, or resolving a customs clearance question, you will get a technically informed answer — not a scripted response.
From setup to scale
We support sellers at every stage: first-time cross-border sellers connecting their store, growing businesses optimizing courier routing, and established brands expanding their logistics network across new European markets. Your success is our success.
Ready to expand globally?
Connect your store for free and start selling across 30+ countries today.