Building Your Finance Tech Stack: A Stage-by-Stage Guide
The right financial tools at each stage of your startup's growth, from pre-seed through Series B and beyond.
Your finance tech stack should grow with your company—not ahead of it, not behind it. Too many startups either cobble together spreadsheets until they're drowning in complexity, or implement enterprise software before they need it.
This guide provides a clear roadmap for what financial tools you need at each stage of growth. We'll cover the core components, specific tool recommendations, typical costs, and when to upgrade. For a comprehensive overview of all financial tools, see our Startup Finance Tech Stack Guide.
Core Principle
Start simple and add complexity only when you genuinely need it. The cost of implementing enterprise tools too early is greater than the cost of migrating later. Your focus should be on building product and growing, not managing sophisticated finance systems.
Building Your Stack: Overview
A complete finance stack includes several interconnected components. Here's how they map to company stages:
| Component | Pre-Seed | Seed | Series A | Series B+ |
|---|---|---|---|---|
| Accounting | QBO Simple | QBO Plus | QBO Advanced | NetSuite |
| Expense Mgmt | Personal card | Ramp/Mercury | Ramp/Brex | Airbase |
| Payroll | - | Gusto | Gusto/Rippling | Rippling |
| FP&A | Spreadsheet | Spreadsheet | FP&A Tool | Enterprise FP&A |
| Bill Pay | Bank bill pay | Ramp/QBO | Bill.com | Bill.com/Airbase |
Pre-Seed / Bootstrapped (0-5 Employees)
The Essentials Stage
At this stage, your finance stack should be minimal. You're focused on building product and finding customers, not managing financial systems. Keep it simple.
Recommended Stack
Accounting: QuickBooks Online Simple Start
The most basic QuickBooks plan is enough. Track income, expenses, and connect your bank. You can handle your own books at this stage or use a cheap bookkeeping service.
Banking: Mercury or Traditional Bank
Mercury offers modern banking designed for startups with a clean interface, free wires, and basic cards. Traditional banks work fine too, but Mercury's integrations are better.
Expenses: Personal Card or Mercury
Many founders use personal cards and reimburse themselves at this stage. If you want separate, Mercury's IO cards work well and integrate with their banking.
Payments: Stripe
If you're collecting payments, Stripe is the default choice. Easy setup, good documentation, and integrates with everything.
What You Don't Need Yet
- Dedicated expense management (Ramp, Brex)—too early
- Payroll software (until you hire employees)
- FP&A tools—a spreadsheet is fine
- Bill.com or AP automation
Total Monthly Cost: ~$30-$50
Your finance stack at pre-seed should cost almost nothing. Save your runway for product and growth.
Seed Stage ($1M-$3M Raised, 5-15 Employees)
The Foundation Stage
Now you have real money and employees. It's time to build a proper foundation. Get the basics right now, and you'll save months of cleanup later.
Recommended Stack
Accounting: QuickBooks Online Plus
Upgrade to Plus for multi-currency, projects, and budgeting. Hire a bookkeeper (part-time or service) to keep books clean. This is foundational—don't skimp here.
Expense Management: Ramp
Time to get proper expense management. Ramp is free, offers 1.5% cashback, and automates accounting sync. Issue cards to employees, capture receipts automatically, and eliminate manual reconciliation.
Payroll: Gusto
Essential once you have employees. Gusto handles payroll, taxes, benefits, and basic HR. Integrates directly with QuickBooks. Set it up before your first employee starts.
FP&A: Spreadsheets (for now)
You still don't need dedicated FP&A software. A well-structured Google Sheet for forecasting and runway tracking is sufficient. Focus your budget elsewhere.
Key Actions at Seed
- Set up proper chart of accounts—structure it right from the start
- Establish monthly close process—books closed within 10 business days
- Implement expense policies—even informal ones help
- Track runway religiously—know your cash position always
- Start building investor data room—organize documents now
Total Monthly Cost: ~$400-$800
(QuickBooks $90 + Ramp Free + Gusto ~$200-$300 + Bookkeeper $500-$1,500)
Series A ($5M-$15M Raised, 15-50 Employees)
The Scaling Stage
You're scaling now. Board meetings require better reporting, investors want detailed metrics, and your finance team needs real tools. Time to professionalize.
Recommended Stack
Accounting: QuickBooks Online Advanced
Upgrade for more users (25), custom fields, batch transactions, and advanced reporting. Start evaluating NetSuite for Series B, but don't migrate yet unless you have clear triggers.
Expense Management: Ramp or Brex
Ramp remains great, but consider Brex if you need higher limits or travel rewards. Add approval workflows, department budgets, and procurement rules.
Payroll: Gusto Plus or Rippling
Gusto Plus handles growing teams well. Consider Rippling if you want unified HR/IT or are hiring frequently and value onboarding automation.
FP&A: Dedicated Tool
Now is the time for real FP&A software. Mosaic, Runway, or Jirav connect to your accounting and provide automated forecasting, scenario planning, and investor-ready reports.
Bill Pay: Bill.com or Ramp
If you have significant vendor payments, dedicated AP automation saves time. Bill.com is the standard; Ramp now offers bill pay built in.
Key Actions at Series A
- Consider a fractional CFO—strategic guidance beyond bookkeeping
- Implement formal budgeting—department-level budgets and accountability
- Build investor reporting cadence—monthly updates, quarterly board decks
- Establish financial controls—approval workflows, expense policies
- Start Series B preparation—clean data room, polished metrics
Total Monthly Cost: ~$3,000-$8,000
(QBO $200 + Expenses Free + Payroll $500-$1,500 + FP&A $500-$2,000 + Controller $2,000-$5,000)
Series B+ ($15M+ Raised, 50+ Employees)
The Enterprise Stage
You're a real company now. Audit requirements, complex compliance, potential M&A or IPO on the horizon. Your finance stack needs to match your sophistication.
Recommended Stack
Accounting: NetSuite or Sage Intacct
Time to migrate to enterprise ERP. NetSuite for full ERP needs, Sage Intacct if your needs are primarily financial. Plan 4-6 months for implementation.
Spend Management: Airbase
Consider Airbase for enterprise-grade spend management with advanced procurement workflows, pre-purchase approvals, and comprehensive audit controls.
HR/Payroll: Rippling
Rippling's unified HR/IT/Payroll platform shines at scale. Automated onboarding, device management, and app provisioning save significant time.
FP&A: Enterprise Tools
Enterprise FP&A tools like Anaplan, Adaptive Planning, or Planful for complex planning, multi-entity consolidation, and board-ready analytics.
Key Actions at Series B+
- Hire full-time finance leadership—VP Finance or CFO
- Prepare for audit—SOC 2, financial statement audit
- Implement SOX-like controls if IPO is potential path
- Build finance team—dedicated accounting, FP&A, treasury roles
- Evaluate treasury management—cash optimization, yield strategies
Total Monthly Cost: ~$10,000-$30,000+
(NetSuite $3-10K + Spend Management $500-2K + Payroll $2-5K + FP&A $2-10K + Team salaries)
Integration Architecture
Your tools should work together seamlessly. Here's how data should flow:
Revenue
Stripe
Accounting
QuickBooks
FP&A
Mosaic
Expenses
Ramp
Accounting
QuickBooks
FP&A
Mosaic
Payroll
Gusto
Accounting
QuickBooks
FP&A
Mosaic
Your accounting system is the single source of truth. Everything flows into it, then FP&A tools pull from it for analysis.
Integration Best Practices
- Use native integrations when available—more reliable than third-party
- Map chart of accounts consistently across all tools
- Test integrations monthly—they can break silently
- Document your architecture so anyone can understand the flow
- Assign an owner responsible for data integrity
Planning for Migrations
Some tool migrations are inevitable as you grow. Plan for them:
Low-Pain Migrations
- Expense management (Ramp ↔ Brex ↔ Airbase): 1-2 weeks
- Payroll (Gusto ↔ Rippling): 2-4 weeks, time to fiscal year
- FP&A tools: 2-4 weeks, data transfers easily
High-Pain Migrations
- QuickBooks → NetSuite: 4-6 months, significant investment
- Any mid-year accounting migration: Avoid if possible
Timing Migrations
Plan major migrations (especially accounting) to coincide with fiscal year start. Avoid migrating during fundraising, audit season, or other high-stress periods. Budget 25-50% more time than vendors estimate.
Cost Summary by Stage
| Stage | Team Size | Tools Only | + People |
|---|---|---|---|
| Pre-Seed | 0-5 | $30-$50/mo | $30-$50/mo |
| Seed | 5-15 | $200-$400/mo | $700-$1,900/mo |
| Series A | 15-50 | $1,000-$3,000/mo | $3,000-$8,000/mo |
| Series B+ | 50+ | $5,000-$20,000/mo | $10,000-$30,000+/mo |
* "People" includes bookkeeper/controller costs, not full finance team salaries
Dive Deeper
Startup Finance Tech Stack Guide
Complete overview of all tools
QuickBooks vs Xero vs NetSuite
Accounting software comparison
Expense Management Tools
Ramp vs Brex vs Mercury
Startup Payroll Solutions
Gusto vs Rippling vs Deel
Complete Guide to Fractional CFO Services
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