Brex Controls Setup Guide for Startups: Proactive Guardrails, Approvals, and GL Sync

The 3 Pillars of Brex Spend Control: A Foundational Framework

For a founder at an early-stage startup, the period after closing a funding round is a balancing act. You have capital to build faster, but every dollar now represents a tangible piece of your runway. Old habits like using a shared company card or chasing receipts via Slack create financial uncertainty and do not scale. This is where a proper Brex account setup guide becomes essential. Implementing controls from the start is not about adding bureaucracy; it is about creating a clear framework for disciplined growth. By focusing on three foundational pillars, you can empower your team to spend effectively while maintaining complete control over your cash burn. For broader context, see our Internal Controls hub.

Before configuring settings, it is helpful to understand the philosophy behind how to set up spending controls in Brex. The entire system is built on a framework of three distinct but interconnected pillars: Spend Limits, Approval Workflows, and Accounting Sync. Think of them as a sequence for managing every dollar that leaves the company.

1. Spend Limits (Proactive Guardrails): These are the rules you establish upfront. By setting clear boundaries on cards and budgets, you proactively prevent out-of-policy spending before it happens. This is your first line of defense for controlling cash flow.
2. Approval Workflows (Reactive Safety Net): These are for exceptions. When a purchase request is unusual or exceeds a pre-defined threshold, it gets routed to the right person for a manual review. This acts as a safety net without creating a bottleneck for routine expenses.
3. Accounting Sync (Automated Record-Keeping): This is the final step where every approved transaction, complete with its receipt and categorization, flows automatically into your general ledger. This eliminates manual data entry and ensures your books are always accurate and up-to-date.

This structure can be visualized as a three-step process: setting proactive limits, creating reactive approval flows, and automating the final accounting sync for a complete, controlled spending process.

Pillar 1: How to Set Up Spending Controls in Brex with Scalable Spend Limits

One of the most immediate financial leaks in a growing startup is uncontrolled software-as-a-service (SaaS) spending. Forgotten trials convert to paid plans and unused licenses accumulate, quietly draining your runway. According to a 2023 Vertice report, the average company wastes approximately 20% of its SaaS spend on unused licenses or forgotten subscriptions. Robust Brex card controls provide a direct solution to this problem through vendor-specific virtual cards.

Instead of using a single card for all software subscriptions, you should create a unique virtual card for each vendor, such as AWS, HubSpot, and Figma. Each card can have its own monthly or annual spending limit that matches the contract terms. This simple action provides two major benefits. First, it prevents surprise charges from automatic renewals or tier upgrades. Second, if a card is compromised, you only need to cancel that specific vendor’s card, not a physical card used by multiple employees. This simple step reduces unexpected charges and operational friction.

Practical Examples of Brex Spending Policies

Consider a SaaS startup that is testing a new marketing automation tool with a $500 per month plan. By creating a Brex virtual card with a strict $500 monthly limit and assigning it to the marketing lead, you ensure the cost never escalates without a deliberate conversation. If the vendor tries to charge for a higher tier, the transaction is automatically declined.

Similarly, a biotech startup can issue a vendor card for a key lab supplier like Thermo Fisher. They can set a quarterly budget, allowing scientists to order necessary reagents without needing individual approval for every small purchase, while still controlling the total R&D spend. The reality for most Pre-Seed to Series B startups is more pragmatic: begin with strict Brex spending policies for your top five SaaS vendors. You can expand from there as you gain confidence in the system.

Pillar 2: Building Brex Approval Workflows That Empower Your Team

Approval workflows are the safety net, not the fence. If your spend limits are the proactive guardrails, approvals are the reactive system for handling exceptions. The goal is to review what matters without making the founder a bottleneck for every purchase. The key is to design Brex approval workflows that are appropriate for your company’s current stage and complexity.

What founders find actually works is starting with a simple, high-threshold system and adding layers of complexity only as needed. Here is a practical, stage-based approach to building your workflow:

• Lean Startup (Pre-Seed/Seed, <15 employees): At this stage, you need visibility, not bureaucracy. A common setup is a single-step approval process. Any transaction over a significant threshold, for example, $1,000, requires approval from a founder. Additionally, any request for a new recurring software subscription, regardless of its cost, should also trigger an approval request. This keeps founders aware of new financial commitments without getting bogged down in approving every routine expense that falls within established employee spending limits Brex allows.
• Scaling Startup (Series A/B, 15-50 employees): As you hire functional leaders, you can introduce role-based, multi-step approvals. For instance, a marketing specialist's request for a new ad campaign budget over $5,000 might first route to the Head of Marketing. Only after their approval does it go to the COO or founder for final sign-off. This empowers department heads to manage their own budgets, freeing up founder time to focus only on the most critical strategic expenditures. You can easily configure these rules in Brex based on amount, merchant, or expense category.

This approach allows you to manage by exception. If a purchase is within the pre-set limits you defined in Pillar 1, no approval is needed, empowering your team to move quickly. Implementing these controls also establishes segregation of duties, which is a core internal control. As explained by institutions like the University at Buffalo, segregation of duties helps prevent a single person from controlling multiple phases of a transaction, reducing risk.

Pillar 3: Mapping Categories for a Clean, One-Click GL Sync

Nothing complicates month-end close for a lean finance function more than a flood of uncategorized transactions. The third pillar of a strong Brex setup is designed to solve this permanently, ensuring every transaction syncs cleanly with your general ledger (GL) in an accounting system like QuickBooks. This is where you connect your startup expense management tools into a cohesive system.

The critical distinction to understand is between user-facing 'Brex Categories' and your official, backend 'Chart of Accounts'. An employee making a purchase does not need to know the specific GL account number for 'R&D Software'. They just need a simple, intuitive category to choose from, like "Software." The power of the integration is mapping that simple category to a precise account in your books.

How Category Mapping Works in Practice

For a US-based deeptech startup, meticulous R&D cost tracking is essential for tax credits under US GAAP. A scenario we repeatedly see is an engineer purchasing a specialized data modeling license. In Brex, they select the "R&D Software" category. Because you have already mapped this category in the Brex dashboard, it automatically syncs to the "7210 - R&D: Software & Tooling" account in QuickBooks. There is no manual re-coding required by you or your accountant.

An e-commerce startup using Shopify can apply the same logic. A new application for the store might be categorized by the user as "Marketing Software." In your Brex settings, you map this to the correct account in QuickBooks, perhaps "6150 - COGS: Platform & App Fees." In the Brex dashboard, you can visually map each category, ensuring that a simple selection by an employee translates into precise accounting data. This automated record-keeping aligns with expectations for financial documentation, such as the general principles outlined in IRS guidance. When it’s time to close the books, the process becomes a one-click sync, not a week-long data entry project.

A Phased Brex Account Setup Guide for Startups

A complete Brex rollout can feel overwhelming, but a phased approach makes it manageable for any startup founder or operator handling finance. Here is a simple implementation plan based on the three pillars.

1. Phase 1 (Your First Week): Lock Down Cash Burn. Start with Pillar 1. Your most urgent task is controlling recurring spend. Identify your top 10 SaaS vendors and create dedicated, limited virtual cards for each one. This action alone will prevent budget creep and give you immediate visibility into your largest operational expense category.
2. Phase 2 (Your First Month): Automate Your Bookkeeping. Next, focus on Pillar 3. Before transaction volume builds up, connect Brex to your QuickBooks account. Take the time to thoughtfully map the default Brex Categories to your existing Chart of Accounts. Getting this data flow correct from the beginning prevents the accumulation of technical debt in your accounting.
3. Phase 3 (As You Scale): Introduce Smart Approvals. Finally, implement Pillar 2 gradually. Do not start with a complex, multi-layer approval system. Begin with a single, high-threshold rule, such as requiring founder approval for any non-recurring expense over $2,000. As your team grows and you hire department heads, you can add more granular, role-based workflows.

Ultimately, a well-configured Brex account is a strategic asset. It provides the financial discipline investors expect while giving your team the autonomy they need to execute. It is a foundation for scalable, disciplined growth. Learn more at the Internal Controls hub.

Frequently Asked Questions

Q: Can I set different spending policies for different teams in Brex?
A: Yes. Brex allows you to create specific policies for different departments or teams. For example, you can set a higher monthly travel budget for the sales team than for the engineering team, ensuring that employee spending limits in Brex are tailored to each group's specific needs and responsibilities.

Q: How does Brex handle receipt collection and management?
A: Brex automates much of the receipt collection process. Users can reply to a text or email notification with a photo of the receipt, or forward digital receipts directly. The system uses AI to match the receipt to the correct transaction, significantly reducing the manual work needed to keep records compliant.

Q: What is the difference between a budget and a spend limit in Brex?
A: A spend limit is a hard cap on a card or user that declines transactions that exceed it. A budget is a soft tracking mechanism for a group of expenses, often for a team or project. Budgets provide visibility into spending against a target but do not automatically decline transactions.

Q: Is setting up Brex spending controls difficult for a non-finance founder?
A: No, the platform is designed for a user-friendly Brex account setup guide. The three-pillar approach of limits, approvals, and sync provides a logical structure. Starting with simple rules and adding complexity only as you scale makes the process manageable for founders without a deep finance background.