Welcome to Seller Bookkeeping
Starting an online business is exciting, but without proper financial setup, you'll face tax surprises, compliance issues, and hidden profitability problems. This guide walks you through the essential first steps every new seller must take.
Whether you're launching Amazon FBA, Shopify, or selling across multiple channels, follow this roadmap to build a business on solid financial ground.
Phase 1: Business Foundation (Weeks 1-2)
Step 1: Choose Your Business Structure
Your choice affects taxes, liability, and complexity. Most new sellers start with one of these:
| Structure | Liability | Taxes | Best For |
|---|---|---|---|
| Sole Proprietor | Personal liable | Schedule C (15.3% SE tax) | Solo starters under $100K |
| LLC | Protected | Schedule C or S-Corp election | Most growing sellers |
| S-Corp | Protected | Lower SE tax on distributions | Sellers with $80K+ profit |
Step 2: Register Your Business
- Choose Business Name: Should reflect your niche (e.g., "TechAccessories LLC")
- File Formation Documents: Secretary of State (cost: $50-150)
- Get EIN: Apply free at IRS.gov (takes minutes)
- Open Business Bank Account: Separate from personal (required for bookkeeping)
Step 3: Register for Seller Accounts
- Amazon Seller Central: Professional seller account ($39.99/month)
- Sales Tax Permits: Register in states where you have nexus
- State & Local Licenses: Check your locality's requirements
⏰ Timeline: 1-2 weeks for LLC + EIN + bank account
💰 Cost: $150-500 total
Phase 2: Accounting Setup (Weeks 2-3)
Step 1: Choose Accounting Software
Compare QuickBooks Online and Xero based on your needs:
- QuickBooks Online ($30-200/month): Better for beginners, integrated US tax
- Xero ($13-70/month): Better for multi-channel, lower cost, faster reconciliation
Recommendation for new sellers: Start with Xero (cheaper while scaling) and switch to QB later if needed.
Step 2: Set Up Chart of Accounts
Create account categories for your business type:
Asset Accounts:
- Business Bank Account
- Inventory (for FBA)
- Equipment
Income Accounts:
- Amazon FBA Sales
- Shopify Sales (if multi-channel)
- Refunds & Returns (contra-income)
Expense Accounts:
- Cost of Goods Sold (COGS)
- Advertising & Marketing
- Fulfillment & Shipping
- Software & Subscriptions
- Professional Services
- Office Supplies
Step 3: Connect Bank Account
- Link business bank account to accounting software
- Enable automatic transaction syncing
- Test with first deposit to verify connection
⏰ Timeline: 1 week
💰 Cost: Software only ($13-30/month)
Phase 3: Initial Financial Setup (Weeks 3-4)
Step 1: Connect Seller Platforms
Link Amazon, Shopify, or other platforms to your accounting software:
Amazon Integration:
- Use official connector or Stitch Labs
- Auto-imports sales, fees, payouts
- Cost: $12-20/month for connector
Shopify Integration:
- Xero or QB has built-in Shopify app
- Auto-syncs orders and payouts
- Usually included in subscription
Step 2: Document Your COGS Calculation
Create a spreadsheet tracking landed cost per product:
- Product name/ASIN
- Supplier invoice cost
- Freight per unit (landed cost)
- Packaging & labeling
- Total COGS per unit
Update monthly as you receive new inventory. This is critical for accurate profit calculation.
Step 3: Set Up Inventory Tracking
- Create inventory items in QB/Xero for each SKU
- Enter opening quantity and COGS
- Link to Amazon/Shopify sales
- Monthly inventory reconciliation
⏰ Timeline: 1 week
💰 Cost: Connector if needed ($0-20/month)
Phase 4: Tax Planning (Month 2)
Step 1: Understand Your Tax Obligations
- Income Tax: 10-37% depending on profit (included with federal return)
- Self-Employment Tax: 15.3% on net profit if sole proprietor/LLC
- Sales Tax: Collect and remit based on state nexus
- Estimated Quarterly Taxes: File Form 1040-ES each quarter if expecting $1,000+ owed
Step 2: Calculate Quarterly Estimated Tax
If you expect to owe $1,000+ annually:
- File Form 1040-ES to estimate annual tax
- Pay 1/4 each quarter: April 15, June 15, September 15, January 15
- Penalty if you underpay significantly
Example: Expected $40,000 net profit → $14,000 annual tax → $3,500/quarter
Step 3: Set Up Tax Reserve Account
- Open separate high-yield savings account
- Transfer 25-30% of gross profit monthly
- Never spend tax reserves on business (kept for April filing)
⚠️ Critical: Set aside taxes NOW. Don't wait until April and face a huge bill.
Setup Checklist
Month 1 Tasks
Month 2 Tasks
Monthly Bookkeeping Routine
Every Month (30 minutes):
- Reconcile Bank Account: Match QB/Xero to bank statement
- Review Transactions: Check for errors or miscategorizations
- Update COGS: Record new inventory purchases with landed costs
- Record Platform Fees: Amazon referral fees, FBA fees, payment processing
- Transfer to Tax Reserve: 25-30% of net profit to savings account
Every Quarter (1-2 hours):
- Close the Month: Verify all transactions posted, reconcile inventory
- Generate P&L Report: Review profit and losses by category
- Calculate Quarterly Taxes: Estimate owed, make payments by due date
- Review Cash Flow: Ensure sufficient funds for supplier payments
- Analyze Profitability: By ASIN, platform, or product category
Every Year (Tax Time):
- Gather Documents: All receipts, invoices, bank statements
- Reconcile Inventory: Physical count vs QB/Xero balance
- Prepare 1099s: If you paid contractors $600+
- File Tax Return: Schedule C, Schedule SE, Form 1040
- File Sales Tax Returns: In each state where you have nexus
Common Startup Mistakes
- Not separating business and personal: Mixing finances makes bookkeeping impossible
- Skipping COGS documentation: Leads to inaccurate profit calculations and tax issues
- Not setting aside taxes: April 15 surprise of $10K+ bill with no money
- Choosing wrong business structure: Paying 15% more in taxes than necessary
- Ignoring sales tax obligations: Penalties and back taxes compound quickly
- Using personal email for business: Creates tax audit red flags
- Not tracking deductions: Missing thousands in legitimate business expenses
- Waiting until April to get organized: Tax filing becomes chaotic and expensive
When to Hire Professional Help
| Situation | DIY vs Professional | Cost If Professional |
|---|---|---|
| Just Starting (Under $50K) | DIY with software | Save $1,500-2,500/year |
| Growing ($50-200K) | Monthly bookkeeper recommended | $400-800/month |
| Scaling ($200K+) | Professional accountant required | $2,000-5,000/year |
| Multi-Channel Operations | Professional recommended | $1,500-3,000/year |
| Considering S-Corp Election | Tax professional required | $1,000-2,000 for analysis |
Summary: Getting Started Roadmap
Week 1: Finalize business structure, register business, get EIN
Week 2: Open bank account, setup seller accounts
Week 3: Choose accounting software, create chart of accounts
Week 4: Connect platforms, document COGS, set up tax reserve
Month 2: Make first monthly reconciliation, file quarterly taxes
Ongoing: Monthly 30-min bookkeeping, quarterly taxes, annual tax filing