A legal invoice approval workflow is the set of rules that routes each outside counsel invoice to the right reviewers, in the right order, until someone with enough financial authority approves or rejects it. It decides who sees an invoice first, when it escalates, and what happens when it is rejected. A good workflow gets routine invoices approved in days and sends large or unusual ones to senior approvers automatically. This guide covers how many tiers to use, how approvers are assigned, how escalation and sequential approval work, and how to govern approval authority over time.
What is a legal invoice approval workflow?
A legal invoice approval workflow is a configured process that assigns invoices to reviewers and approvers based on rules, then moves each invoice through those people until it is fully approved or rejected. In Unity, reviewers and followers can be set at the matter, vendor, legal entity, practice area, and invoice level. Billing data from about 400 law firms shows average payment times fell from 62 to 50 days in 2025. Most e-billing platforms build it from three parts.
- Assignment. Rules decide who reviews each invoice first, based on the matter, vendor, legal entity, or practice area.
- Sequence. Where an approval ladder exists, approvers are notified one after another, each after the previous one approves.
- Escalation. When an invoice’s value exceeds the current approver’s authority, a designated escalation approver is added.
These rules sit downstream of your billing guidelines. By the time an invoice reaches an approver, billing guidelines should already be enforced as system rules, so approvers judge value and substance, leaving compliance to the rules.
How many approval tiers should a legal invoice workflow have?
A legal invoice workflow should have as many approval tiers as your financial authority policy requires, and for many corporate legal departments that means three to five. The number is a design choice for your department, since platforms generally let you configure the hierarchy.
A five-tier chain is a common design for larger departments. A typical example looks like this:
- Tier 1: Matter lead or first reviewer. Checks the work was done and the invoice fits the matter, and approves routine invoices within their limit.
- Tier 2: Supervising attorney. Approves invoices above the first reviewer’s authority, such as those over $10,000.
- Tier 3: Senior legal or finance approver. Reviews larger invoices, often above $50,000, with an eye on budget.
- Tier 4: Department or business unit head. Approves spend that affects the unit’s budget, for example above $250,000.
- Tier 5: General counsel or final authority. Signs off the largest invoices, such as those above $1 million.
Use as few tiers as your policy allows. Each added tier typically adds two to five business days to cycle time, so most departments aim for 80 percent or more of invoices to be fully approved at the first or second tier.
How are approvers assigned to legal invoices?
Approvers are assigned to legal invoices through invoice review rules that look at the invoice’s vendor, matter, legal entity, practice area, and escalation level. In SimpleLegal, these rules manage, automate, and control the approval process, so nobody routes invoices by hand.
- Matter reviewers. Matter records can hold assigned reviewers and subscribers, so the person running the matter sees its invoices first.
- Legal entity defaults. A legal entity lead can be set as the default first reviewer for invoices tied to that entity.
- Rule-based routing. Additional rules add approvers by vendor, practice area, or other conditions an administrator defines, such as sending all patent invoices to the IP team.
Keep the rule set small enough to explain on one page. Departments that build 50 or more overlapping rules often find invoices routed to unexpected people, and troubleshooting takes longer than the approvals themselves.
How does threshold-based escalation work for legal invoices?
Threshold-based escalation for legal invoices works by comparing the invoice value with the current approver’s authority limit, and adding a designated escalation approver when the invoice exceeds it. In SimpleLegal, the escalation approver is added to the invoice for validation automatically.
Each approver holds an authority limit, and each limit points to the next approver. An invoice for $35,000 reaching a first reviewer with a $10,000 limit escalates to the supervising attorney, and if that approver’s limit is $50,000, the chain stops there. Set limits in round numbers tied to your delegation of authority policy, and make sure every approver’s escalation path ends with someone who can approve the largest invoice you expect. An escalation path with a gap leaves invoices stranded, usually at month end. Review the thresholds once a year, since limits set at launch drift out of step with inflation, rate increases, and larger matters.
How does sequential approval work in SimpleLegal?
Sequential approval in SimpleLegal works as an approval ladder: the first approver is notified, and once they approve, the next approver in the hierarchy is notified, until the invoice is fully approved or rejected. Each approver sees the invoice only when it is their turn.
This sequence keeps accountability clear. The supervising attorney knows the matter lead has already reviewed the work, and the finance approver knows both legal reviews are complete. Set a target for each tier, such as two business days, and track how long invoices spend at each step. A single approver who takes a week to act will show up clearly in the data, and a delegate can be assigned while they are away. For a broader view of the platform, see how SimpleLegal works as Onit’s mid-market ELM platform.
How can approvers act on legal invoices quickly?
Approvers can act on legal invoices quickly by using the approval route that suits the invoice, whether the invoice details page, email, or bulk approval. Giving approvers the right tools cuts cycle time more than changing the tiers.
- Invoice details page. Shows the full invoice with any verification issues, which suits larger or unusual invoices that need a closer look.
- Email approval. Lets approvers act from their inbox, which suits senior approvers who rarely log in.
- Bulk approval. Lets a reviewer approve many routine invoices at once, which suits month end.
Encourage approvers to check verification issues before approving. These flags point to lines that may breach billing rules, and approving past them without reading usually leads to adjustments later.
What should happen when a legal invoice is rejected?
When a legal invoice is rejected, the vendor should receive a clear reason and know exactly what to correct before resubmitting. In SimpleLegal, rejection information can be communicated to the vendor, and what the vendor sees depends on the options the reviewer selects.
Use a short list of standard reasons, such as wrong matter, unapproved rate, missing detail, or work outside scope, so rejections stay consistent across reviewers. Write each note as if the firm’s billing team will read it, because it often will.
Track rejections by reason and by firm every month. A firm with repeated rejections for the same reason needs a conversation, and a reason that dominates across firms may point to an unclear guideline.
Which invoice statuses should the approval workflow track?
The approval workflow should track a small set of invoice statuses that tell both the department and the firm where each invoice stands. Onit invoice workflows can use statuses such as Received, On Hold, Approved, Paid, and Rejected.
Firms can see whether an invoice has arrived, is paused, has been approved, has been paid, or has been sent back. Agree internally what each status means and who can move an invoice into it, especially On Hold, which should always carry a reason and an owner. Report on invoices that have spent more than 30 days in any status other than Paid, and review that list weekly.
How should approval authority be governed over time?
Approval authority should be governed with a written policy, an owner, and a regular review of limits and approvers. Workflows break quietly when people change roles and nobody updates the chain.
- Written delegation policy. Approval limits in the platform match the company’s delegation of authority policy, and any difference is documented.
- Joiner and leaver updates. Role changes trigger an update to approver assignments within days, so invoices never route to someone who has left.
- Annual review. Limits, escalation paths, and review rules are checked once a year against actual invoice volumes and values.
Run five to ten sample invoices of different values through the updated chain to confirm each lands with the right approver.
Conclusion
A legal invoice approval workflow works when routine invoices clear quickly and large ones reach senior approvers automatically. Match the number of tiers to your authority policy, assign first reviewers through matters and legal entities, and let threshold-based escalation and sequential approval carry invoices up the chain. Give approvers fast ways to act, standard rejection reasons, and clear statuses. Then govern authority limits with a written policy and an annual review, so the chain keeps matching your organization as it changes.
How Basla can help
Basla provides delivery teams for enterprise legal management and eBilling software implementation, covering legal technology consulting, approval workflow design, invoice review rule configuration, testing, documentation, and post-go-live support. For a legal invoice approval workflow, that means mapping your delegation of authority to approval tiers, configuring review rules and escalation paths, and testing each path with invoices at every threshold before go-live.
Basla has delivered matter management and eBilling across 10+ global jurisdictions, where approval chains often vary by legal entity and region. That experience helps departments build approval workflows that stay consistent across every entity.
Frequently asked questions
What is a legal invoice approval workflow?
A legal invoice approval workflow is the set of rules that routes outside counsel invoices to reviewers and approvers in order, until someone with enough authority approves or rejects them. It covers assignment, sequence, and escalation.
How many approval tiers should legal invoices have?
Legal invoices should have as many approval tiers as the department’s authority policy requires, often three to five. Most departments aim for the majority of invoices to be approved at the first or second tier.
How does invoice escalation work in SimpleLegal?
In SimpleLegal, when an invoice’s value exceeds the current reviewer’s approval authority, the designated escalation approver is added to the invoice for validation. Approvers in a hierarchy are then notified in sequence.
How are approvers assigned to invoices in SimpleLegal?
Approvers in SimpleLegal are assigned through invoice review rules based on vendor, matter, legal entity, practice area, escalation level, and other administrator-defined conditions. A legal entity lead can also be the default first reviewer.
Can legal invoices be approved by email?
Legal invoices in SimpleLegal can be approved by email, from the invoice details page, or through bulk approval. The details page also shows verification issues that may need attention before approval.
What happens when a legal invoice is rejected?
When a legal invoice is rejected, rejection information can be communicated to the vendor, and what the vendor sees depends on the options the reviewer selects. Clear reasons help the firm correct and resubmit quickly.
*This article is provided for general information only and does not constitute legal advice. Basla Solutions provides legal technology implementation and support services and does not practice law.*