A payment processor such as BILL or Melio moves the money for you: it debits your bank account, holds the funds while they settle, and pays the other party from its own accounts, charging a subscription plus a fee per payment. ACH file software such as FiSTWorks never touches the money: it builds the NACHA file that your own bank processes, for a flat subscription with no per-payment fee. Choose a processor when you cannot or do not want to originate ACH through your bank. Choose file software when you can, and you want the money to move bank to bank under your control.
Competitor prices and fees in this post were read from bill.com and melio.com on 2026-10-29. Both companies change them; check their pricing pages before deciding.
Two different kinds of product
A payment processor sits between you and your bank. You approve a bill in its app, it pulls the money from your account, and it pays the vendor by ACH, card, or a check it prints and mails. The vendor often has to join the processor's network or accept a payment link. BILL and Melio are the two best-known examples for small businesses.
ACH file software builds the file that banks already accept. You keep your recipients and bank details in it, it writes the 94-character NACHA records, checks them against the rules, and you send the file to your bank through the bank's portal or over SFTP. Your bank moves the money. ACH Drafter is this kind of product.
The distinction matters more than the feature lists, because it decides who holds your money, what you pay, and what your bank needs to know about you.
Who holds and moves the money
With a processor, there is a middle step. BILL's developer documentation describes it plainly: on the process date "BILL debits funds from your funding account", then "BILL waits 2-3 US business days for debit settlement", and "when BILL receives your funds, BILL credits the vendor bank account". BILL quotes 2 to 4 business days end to end for ACH. Melio says standard payments scheduled before 9 p.m. ET "arrive within 3 business days" and that it works with partner banks to process them. In both cases the money leaves your account before it reaches the vendor, and the processor's accounts sit in between.
With your own NACHA file, there is no middle step. Your bank receives the file, submits the entries to the ACH network, and the funds settle directly between your account and the vendor's or customer's account on the effective date you chose. FiSTWorks never holds or moves money. Your bank makes the final decision on every file and every payment.
Both processors also offer faster options at a higher price: same-day or instant delivery for a percentage of the amount. Your bank may offer same-day ACH too, usually for a fee it sets.
What it costs
Processor pricing has two parts: a subscription and a fee per payment. As of 2026-10-29:
| BILL (AP & AR) | Melio | |
|---|---|---|
| Subscription | Essentials $49, Team $65, Corporate $89, each per user per month; Enterprise custom | Go $0 (one user), Core $25, Boost $55, Unlimited $80 per month; Platinum custom; annual billing is cheaper |
| Standard ACH payment | $0.59 each | 5, 20, 50 or unlimited free per month by plan, then $0.50 each |
| Mailed check | $1.99 each | $1.50 each |
| Faster ACH | Pay Faster ACH $11.99; instant 1% ($9.99 min, $100 max) | Same-day ACH 1% ($75 max); instant 1% ($75 max) |
| Paying by card | 2.9% | 2.9% |
| Failed payment | Failed ACH after receiver paid $50; re-debit $25 | Not listed on the pricing page |
For a business that pays 200 vendors a month on standard ACH, the per-payment fees alone come to $118 at BILL or $90 at Melio Core (180 payments after the 20 free ones), before the subscription.
ACH file software is a flat subscription with no per-payment fee, because the only party moving money is your bank, which already charges you for ACH origination under your own agreement. FiSTWorks plans and what each includes are on the pricing page. Your bank's origination fee is the other number to ask about: most banks charge a monthly fee for the service and some charge per file or per item, and that applies whichever software you use.
When a processor is the right answer
Be honest about this one, because for some businesses it is.
- Your bank will not set you up for ACH origination, or the approval would take months. Processors run under their own bank relationships, so you can start paying by ACH without one.
- You want the vendor to choose how they get paid. Processors mail checks, pay by card and handle international vendors from the same screen. File software produces domestic ACH entries only.
- You want bill capture and approval workflows in the same tool. Both BILL and Melio are accounts-payable products first. Capturing invoices, routing approvals and syncing to the ledger is their core, and the payment is the last step.
- Your volume is tiny. Melio's free plan includes a handful of ACH payments a month, and at that volume per-payment fees do not add up to much.
When your own bank is the right answer
- You already originate ACH, or can. Property managers, payroll-running businesses and anyone collecting recurring payments usually can, because banks approve origination for exactly these uses.
- You pay or collect from the same people every cycle. Per-payment fees are a tax on volume. The 200-payment example above pays for a year of file software in a few months.
- You collect money, not just pay it. With a processor, your customer pays an invoice or a payment request through the processor's system. With your own file, you debit the account the customer authorized, on the date you set, for rent, dues or recurring invoices.
- You run payroll. Direct deposit is a credit file to your bank, the same file software builds for vendor payments. Processors are not payroll tools.
- You want the money to move on your schedule, bank to bank, with no settlement hold in a third party's account and the full record in your own bank's audit trail.
Side by side
| Payment processor (BILL, Melio) | ACH file software (FiSTWorks) | |
|---|---|---|
| Who moves the money | The processor, through its own bank partners | Your bank, from the file you send it |
| Where the money sits in transit | The processor's accounts, for 2 to 4 business days (BILL) or up to 3 (Melio) | In the ACH network between your bank and the receiving bank |
| Pricing | Subscription plus a fee per payment | Flat subscription, no per-payment fee |
| What your bank must provide | A business account to debit | ACH origination approval, a company ID and file requirements |
| Payment types | Domestic ACH, cards, mailed checks, international | Domestic ACH credits and debits (PPD, CCD, CTX, WEB, TEL) |
| Collecting from customers | Invoices and payment requests the customer acts on | Debits you originate against a signed authorization |
| Payroll direct deposit | Not offered | Yes, as a credit file |
| Invoice capture and approvals | Core feature | Approval workflow for drafts; invoices stay in your accounting system |
| Vendor onboarding | The vendor joins the network or accepts a link | You collect routing and account details once |
| Records | In the processor's account | In your bank's statements and the file history |
What FiSTWorks is not
FiSTWorks is not a payment processor, a money transmitter or a bank. It does not hold funds, settle payments or decide whether a payment goes through. It builds, checks and delivers the file. If you need someone to move the money on your behalf, you need a processor or your bank, not file software.
If you are not sure whether your bank will originate ACH for you, ask them before buying anything. The question to ask is "Can my business submit NACHA files for ACH origination, and what do you charge for it?" If the answer is yes, How to Create a NACHA File shows what happens next, and the free ACH Validator will check any file you build.
Sources
- BILL pricing: bill.com/pricing, read 2026-10-29
- BILL payment flow and timing: developer.bill.com, "AP payment disbursement methods", read 2026-10-29
- Melio pricing: melio.com/pricing, read 2026-10-29
- Melio ACH timing: melio.com/ach-payments-online, read 2026-10-29