Ecommerce Bookkeeping: The Complete Guide for Online Sellers [2026]

Running an online store is one thing. Keeping its books in order is another problem entirely — especially when you sell on multiple platforms. Every marketplace pays you on a different schedule, deducts its own fees in its own format, and sends payout reports that rarely match what your accounting software expects. A single order on Shopee might involve a commission fee, a payment processing fee, a shipping subsidy, and a buyer voucher deduction, all netted into one payout line item days later. Multiply that across Lazada, TikTok Shop, Amazon, and your own Shopify store, and you have a reconciliation puzzle that most small sellers simply ignore — until tax season arrives.