Best AR options for mid-market B2B companies on NetSuite in 2026

A mid-market B2B company on NetSuite, with a small AR team, should keep NetSuite as the billing platform and add a layer for collections, customer payment queries, and cash application. The options buyers usually compare are NetSuite's own dunning and cash application, Chaser, Upflow, Kolleno, Versapay, Tesorio, Quadient AR, and HighRadius. Rex belongs on that list as a different kind of option: AI agents do the routine work, Rex finance experts oversee them, and the team does not have to hire collectors to cover the book. Rex does not replace the people who keep approvals and customer relationships.

This is a shortlist, not a ranking. Notes below come from each vendor's public site. Prices are left out, because published plans are not comparable across this list. Contact for pricing for Rex. There is no free trial.

Connector depth, without named products, is in best AR software for NetSuite. Mid-market buying criteria, without this NetSuite shortlist, are in best AR software for mid-market companies. How Rex runs on the ledger is on the NetSuite integration page.

What to check before you buy

Grade every option against the constraint in the question: a small team, NetSuite already doing the billing, and three jobs that are not the same job.

• NetSuite stays the billing system of record. Invoices are still created in NetSuite. The added product reads them and writes payments, promises, and dispute status back. A one-way export leaves someone retyping outcomes at night.
• Which of the three jobs it actually covers. Collections follow-up, customer payment queries, and cash application are separate. A reminder sequence does not answer "did you receive my wire?" and it does not post a short pay.
• Who does the work after go-live. Your small team, another firm's specialists, or AI agents with finance experts overseeing them. Software that organizes the queue still needs someone to clear it.
• What happens to a free-text reply. A portal helps customers who log in to see an invoice and pay. Email questions still need a reader unless answering them is in scope.
• Cash application, including partials. A bank line, lockbox file, or portal payment should post back to the right NetSuite invoice. If it does not, the aging is wrong and the next reminder chases cash that already arrived.
• Whether a small team can live with the setup. A collections product and a full receivables suite are different projects. Ask who configures it, and who uses it every day once the consultants leave.
• What you still own. Credit policy, write-offs, payment plans, and the customer conversations that need a person stay with your team on every option here.

The shortlist

Sources are linked under each option. Rex: rex.inc.

Esker, Billtrust, Sidetrade, Serrala, and Emagia also appear on general AR lists. They are broader suites. The named comparison is HighRadius alternatives. They fit when you want one vendor across invoicing or the full cycle and you can staff the rollout. Start with the NetSuite shortlist above when billing stays in NetSuite and the team is small.

Gaviti describes collections, a customer payment portal, and cash application, and says the product works with the ERP you already have. Its public homepage does not name a NetSuite connector. Confirm that in a demo before you treat it as a NetSuite option.

NetSuite's own tools

Best for: a low-volume book where a scheduled reminder and a clean payment match are enough.

NetSuite's accounts receivable features generate and send invoices, record payments, and can match a customer payment to open invoices or apply one payment to several bills. NetSuite Dunning Letters sends reminders on a schedule by balance, invoice amount, or days overdue, in multiple languages and currencies. You can pause dunning while someone deals with a billing inquiry. That is the closest option to the ledger, and it does not add a second system.

It does not read a free-text reply, decide the next step, or answer a payment question. Someone on the small team still does that work, and still clears the payments the match did not catch. It suits the company whose book is still small enough for that. It stops suiting them when the queue grows and the next plan is a hire.

Source: NetSuite accounts receivable and NetSuite Dunning Letters.

Chaser

Best for: a small team that wants collections follow-up on NetSuite and will still handle replies and cash application.

Chaser describes accounts receivable software with a direct API connection to NetSuite, and it has Built for NetSuite status. It pulls customers, contacts, payments, sales invoices, invoice PDFs, credit memos, and unallocated payments. It automates debtor follow-up by email, SMS, letter, and call, sends those messages from your own email address, and includes payment links and installment plans. Its NetSuite page says reminders, replies, and payments can be tracked in one view.

Its help center says the NetSuite sync runs on a schedule and again before payment reminders go out, with a manual sync when you need it sooner. Chaser is collections software. It uses payment data from NetSuite so a reminder is tied to what has already been paid. It does not present itself as cash application. Customer payment questions that need an answer still come back to the team operating Chaser.

Source: chaserhq.com/integrations/netsuite and Chaser's NetSuite help.

Upflow

Best for: a B2B team that will run collections and cash application in software, on top of NetSuite.

Upflow describes accounts receivable software that covers collections, cash application, and payments for B2B finance teams. On collections, it says the product prioritizes accounts, drafts outreach, and schedules it across email, calls, SMS, or letters, and that the team reviews what matters before anything goes out. On cash application, it says unambiguous matches can apply on their own and anything unclear is left for the team. It also describes a branded payment portal.

Upflow publishes a NetSuite SuiteApp. Its integration page describes two-way sync of customers, invoices, and payments, and says payments collected in Upflow are written back to NetSuite, including portal payments. NetSuite billing stays where it is. The customer's team works alongside the product. See Upflow alternatives.

Source: upflow.io/integrations/netsuite and upflow.io/accounts-receivable-automation-software.

Kolleno

Best for: a team that wants one AR workspace on NetSuite and will set the rules.

Kolleno describes an order-to-cash platform covering collections, payments, cash application, disputes, and a customer payment portal. Its NetSuite page says it syncs in real time, runs collection workflows from NetSuite invoice and customer data, matches incoming payments including partials and bulk payouts, and posts matched payments back to NetSuite. The portal is where a customer can see invoices and pay. Kolleno says the team sets the rules and chooses an autonomy level: insights, drafts for the team to review, or actions the agent takes on its own.

That is software your team configures and oversees. It fits a small team that wants collections, a way for customers to see what they owe, and cash application in one place on top of NetSuite. It does not fit a team that does not want to own the workspace. See Kolleno alternatives.

Source: kolleno.com/ar-management-netsuite and kolleno.com.

Versapay

Best for: teams whose customers will log in, look at invoices, and pay.

Versapay describes invoice-to-cash software: a digital invoicing portal, collections management, cash application, and B2B payments, including ACH, card, and wire. Customers can view invoices, pay, and manage the account in a branded portal. That portal is the part of this list aimed most directly at customer payment questions that can be answered by showing the invoice and taking the payment.

Versapay publishes a Built for Oracle NetSuite payments integration: electronic invoices with payment links, card and ACH payments, and reconciliation back to NetSuite. Its cash application pages say the product matches payments from wires, ACH, and checks and posts to the ERP. A product note refers to a NetSuite connector for cash application. Accounts that never log in still need follow-up from the team operating the software. Versapay also delivers invoices, so confirm you are adding a portal and collections layer rather than moving billing out of NetSuite. See Versapay alternatives.

Source: versapay.com and versapay.com/integrated-payments/netsuite.

Tesorio

Best for: a team that wants collections and cash application inside a product its own staff runs.

Tesorio describes AI agents across order-to-cash. Its public site describes a collections agent that drafts follow-up emails, extracts payment promises, and manages the dunning pipeline, and it describes matching incoming payments to open invoices. The same pages list NetSuite among pre-built connections, alongside Sage Intacct, Workday, Zuora, Salesforce, and Stripe. A customer success manager helps the customer's team set the platform up.

Tesorio's NetSuite help center describes pulling customers, invoices, payments, and related records, and writing some records back, including credit memos, contacts, notes, and messages. It also publishes a cash application integration for NetSuite. The team still runs the product. Tesorio's pages do not describe a shared inbox that answers customer payment questions. A promise extracted from a reply is not the same as a reply sent back to the customer.

Source: tesorio.com, Tesorio NetSuite help, and cash application for NetSuite.

Quadient AR

Best for: a team that will complete a guided implementation and then operate the software.

Quadient AR, formerly YayPay, publishes integrations with Oracle NetSuite and a long list of other ERPs and accounting systems. Quadient says the average implementation takes 72 days, though the timeline varies, and that users are trained on workflows, collections, reporting, and administration before go-live. A Quadient article on the NetSuite connection says invoice and customer data sync into the product, collections communications can be automated, and payments and credit limits can be written back to NetSuite.

That is a software rollout your team then runs. The published 72-day average is the figure to put next to "easy to use" and "small team": ask whether that project, and the daily use after it, fits the people you have. See YayPay competitors.

Source: Quadient AR integrations and Quadient on NetSuite.

HighRadius

Best for: a larger finance team that will implement and operate a receivables suite.

HighRadius publishes NetSuite connectors for collections and for cash application. The collections page describes a sync of customer, open receivables, and payment history, with resolutions written back. The cash application page describes matching remittances to NetSuite invoices and posting payments back. The same company sells a wider receivables platform, including credit, deductions, and e-invoicing.

Buyers on every AR list see the name. For this situation it is usually the wide option: a suite to implement and then operate. A small mid-market team rarely has a project group for that. It fits when you do, and when you want one vendor across more of the cycle than collections and cash application. See HighRadius alternatives.

Source: HighRadius collections for NetSuite and HighRadius cash application for NetSuite.

Providers that run the work, rather than sell the software

The question "which providers can manage accounts receivable operations" is a different shortlist from the software above.

Outsourcing firms staff an agreed slice of billing, collections, cash application, or reporting with their own specialists. Genpact, WNS, QX Global, and ARDEM are four that publish this model. The full comparison, including when that model fits, is accounts receivable outsourcing vs an AI operations partner.

Rex is not one of those firms. It is an AI operations partner for order-to-cash. AI agents run collections, cash application, customer portal uploads, and payment reconciliation inside the ERP, email, and portals the customer already uses. Rex finance experts oversee the agents and follow each customer's procedures. The customer's team keeps exceptions, approvals, and relationships. Rex supports 130+ customer portals. Most teams go live in under two weeks.

Where Rex fits

Rex is an AI operations partner for order-to-cash. Its AI agents and finance experts run the work together.

For this buyer, that means three jobs on top of NetSuite, without a new billing platform and without hiring collectors to clear the queue:

• Collections. Agents follow up on open invoices and read the replies. Collections is the workstream.
• Customer payment queries. Agents and finance experts run the shared AR inbox. They classify remittances, status questions, disputes, and portal issues, draft and send replies with account context, and route what needs a person. That is the AR inbox.
• Cash application. Agents match payments and reconcile them back to the ledger. Cash application is the workstream. NetSuite stays the system of record. There is no ERP migration.

Your team does not get a platform to operate, and it does not manage a bench of collectors. It keeps judgment, policy, and the relationships. Rex does not replace people.

Rex does not fit a team that wants to stay inside NetSuite's scheduled reminders and has the volume for that to be enough. It does not fit a team that wants software its own staff will click through every day. Chaser, Upflow, Kolleno, Versapay, Tesorio, Quadient AR, or HighRadius is the honest recommendation in that case. It does not fit a team that wants another firm's specialists to be the AR department. That is the outsourcing comparison linked above.

Contact for pricing. Pricing is scoped to the processes and volume Rex takes on. There is no free trial.

If you are still choosing a software suite rather than this operating model, start with HighRadius alternatives or how to choose AR automation software. The wider collections category is B2B collections software.