If you run a B2B business, you already know the drill: you send an invoice, and then... you wait. Some customers pay on time. Others need a reminder. A few need three reminders, a phone call, and a slightly awkward email. Someone on your finance team has to track all of this in a spreadsheet, decide who to chase and when, and follow up without sounding like a debt collector. This whole process is called "accounts receivable" (AR) — and in 2026, a new wave of AI tools is taking over the chasing, the reminders, and even the awkward conversations, so your team can focus on the invoices that actually need a human.
We looked at five real AR and collections tools built for different company sizes and levels of automation — from a free-forever dashboard for small teams to fully autonomous AI agents that negotiate payment terms on their own. Here's how they actually compare, with real pricing and honest trade-offs.
| Tool | Best for | Pricing | Free tier? |
|---|---|---|---|
| Upflow | Teams that want a modern AR dashboard without an AI agent | Free forever, then quote-based by ARR | Yes, real free tier |
| Tesorio | Enterprise finance teams with high invoice volume | Quote-based, 100% enterprise | No |
| Centime | Mid-market teams who want AP + AR + cash forecasting in one place | Quote-based, billed by volume | No |
| Stuut | Enterprises that want a fully autonomous collections agent | Quote-based, demo required | No |
| Lunos AI | Finance teams who want transparent, published pricing | 0.3% of collections, or $15k/yr flat | No, but pay-as-you-go from day one |
What "AI accounts receivable" actually means
Not all five tools do the same job. Some are dashboards that automate reminders and give you visibility (Upflow, Tesorio, Centime). Others are AI agents that act more like a collections employee — reading replies, resolving disputes, and applying payments on their own (Stuut, Lunos AI). Knowing which category you need matters more than any single feature comparison.
Upflow: the best starting point, and it's genuinely free
Upflow calls itself a "financial relationship management" platform, which is a fancy way of saying: it gives your finance team a real-time dashboard of who owes you money, automates the reminder emails, and includes a branded payment portal (card, ACH, wire) so customers can just pay from the email you send them. The standout feature here is the free "Discover" tier — it's free forever, not a 14-day trial, which is rare in this space.
Forces: a real free tier, a modern interface built for finance teams (not repurposed CRM software), and a white-labeled payment portal.
Limits: there's no autonomous AI agent handling disputes or negotiation — it automates reminders, but a human still resolves anything complicated. Paid tiers are quote-based rather than published.
Verdict: pick Upflow if you want to stop chasing invoices in spreadsheets without committing budget upfront. It's the easiest tool on this list to just try today.
Tesorio: built for enterprise volume
Tesorio is an order-to-cash platform aimed squarely at CFOs and controllers at mid-market to enterprise companies pushing a large volume of B2B invoices. Its standout feature is AI-driven cash application — automatically matching incoming payments to the right invoices, which is a genuinely tedious manual task at scale — plus real-time cash flow forecasting.
Forces: automated cash application, real-time forecasting, and built to handle serious invoice volume without falling over.
Limits: no published pricing (expect a sales cycle), and no free tier at all — this isn't built for small teams.
Verdict: pick Tesorio if you're an enterprise finance team drowning in reconciliation work and cash forecasting, not a startup looking for a quick fix.
Centime: AP and AR in one subscription
Centime takes a different angle: instead of specializing in receivables, it bundles accounts payable, accounts receivable, cash flow forecasting, and expense management into one platform for mid-market finance teams (roughly $10M–$250M revenue, per their own targeting). Pricing is based on invoice volume processed rather than per-user seats, and expense management is included at no extra cost.
Forces: one platform instead of stitching together AP + AR + expenses tools, and volume-based pricing rather than a per-seat tax on growing teams.
Limits: being a generalist means it's less specialized than a tool built only for collections, and like most of this category, pricing is quote-only.
Verdict: pick Centime if you'd rather consolidate finance tooling than run separate AP, AR, and expense apps.
Stuut: an AI agent that actually chases the money
Stuut is built around a specific idea: instead of automating reminder emails, let an AI agent handle the entire collections conversation — chasing payments, resolving disputes and deductions, and applying cash, the way a human collections rep would. It's aimed at enterprise organizations with a meaningful volume of receivables where a dedicated agent's time is worth automating.
Forces: genuinely autonomous (not just automated reminders), it also handles disputes and deductions rather than just chasing, and integration is pitched as fast to set up.
Limits: zero public pricing, so you can't evaluate cost without booking a demo, and the "fully autonomous" promise is worth testing carefully before trusting it with customer relationships.
Verdict: pick Stuut if you want to replace — not just assist — a chunk of manual collections work, and you're comfortable vetting an early-stage AI agent through a sales process.
Lunos AI: AR and AP agents with transparent pricing
Lunos AI is the other autonomous-agent option on this list, but with a meaningful difference: it publishes its pricing. You can start pay-as-you-go at 0.3% of what it collects (up to $5M in receivables), move to a $15k/year flat plan up to $10M, or go enterprise beyond that. It also covers both AR and AP, and can be reached over Slack or email instead of forcing your team into a separate app.
Forces: transparent, published pricing (rare for AI collections agents), covers both receivables and payables, and works through channels your team already uses like Slack.
Limits: the entry-level pricing is a commission that grows with volume rather than a flat fee, and the cheapest tier caps out at $5M in receivables.
Verdict: pick Lunos AI if you want an autonomous collections agent but need to know the real cost before you talk to sales.
Which one should you actually pick?
If you're a small or mid-size team just trying to get out of spreadsheets, start with Upflow — its free tier means there's no reason not to. If you want an AI agent to genuinely take collections off your plate, Lunos AI is the one with pricing you can actually evaluate before a sales call, while Stuut pushes further into full autonomy for enterprises willing to go through a demo. And if you'd rather consolidate your entire finance stack, Centime and Tesorio both go beyond receivables into cash flow and payables — Centime for mid-market teams wanting AP+AR+expenses together, Tesorio for enterprises with heavy invoice volume and real cash-application needs. None of these are one-click fixes for late payments, but all five will get your team out of manual reminder emails.