Quick answer: Published "starting at $99/month" pricing is roughly 30% of what you will actually pay. Real Year-1 cost is base subscription plus per-payment transaction fees plus implementation, and the pricing model — per-seat, per-invoice, or per-transaction — decides who is cheap at your volume. For 100–1,000 invoices a month with mostly domestic payments, Ramp Bill Pay, Ken, and Melio land under $3,500 a year. Bill.com lands near $14,000. Tipalti, AvidXchange, and Vic.ai sit between $25,000 and $40,000 in Year 1 once implementation is included.

Why list prices lie

Every AP automation vendor publishes a number. Bill.com says "Essentials at $45 per user per month." Tipalti says "starts at $99 a month." Ramp says "free." None of those numbers survive contact with an actual purchase order.

Real cost has three layers:

Platform fee — the published number, billed per user, per entity, or as a flat platform charge.
Transaction fees — per-payment charges that scale with invoice volume. ACH, check, wire, virtual card, international SWIFT. This layer is rarely on the pricing page.
Implementation and integration — one-time setup, ERP connector fees, custom approval flow build-outs. Enterprise vendors charge $5,000 to $50,000 here. Most pricing pages hide it entirely.

The pricing model matters more than the sticker. Per-seat platforms (Bill.com, Concur) get expensive fast as approvers join. Per-invoice platforms (Ken, AvidXchange) stay flat as the team grows but punish high-volume teams that stay small. Per-transaction platforms (Ramp, Melio) reward teams that batch ACH and avoid wires.

We modeled all three at three real volumes so you can stop comparing apples to a fruit basket.

Year-1 total cost at 500 invoices per month

The mid-market case: 500 invoices a month, 6 users (3 AP, 3 approvers), 70% ACH, 20% check, 10% wire or international. This is the volume where pricing models diverge the most.

Real Year-1 Cost at 500 Invoices/Month

Modeled for a mid-market AP team: 6 users, 70% ACH, 20% check, 10% wire/international. Quote-based vendors use the midpoint of public buyer reports. Bars stack platform fees, transaction fees, and first-year implementation.

Sources: Bill.com Corporate plan ($89/user/month, public); Ramp Bill Pay (free tier, transactions waived when paying from Ramp Business Account); Melio Unlimited ($80/month + wire fees); Ken Crew tier ($100/month, transactions bundled); Stampli, AvidXchange, Tipalti, Vic.ai: midpoint of public buyer reports on Vendr, ITQlick, and G2 procurement data. Your quote will vary.

The spread is real. Same workflow, same volume, the most-expensive vendor costs roughly 30× the cheapest. That gap is almost entirely about pricing model, not capability.

Side-by-side pricing matrix

Vendor	Model	Published start	Per-payment fees	Implementation	Best fit
Ken	Per-invoice tiers	$29/mo (50 inv)	Bundled	$0	Slack-first teams, 50–1,000 invoices
Ramp Bill Pay	Free + per-payment	$0	ACH $0.59, check $1.99 (waived from Ramp Account)	$0	Teams using Ramp cards already
Melio	Tiered flat	$25/mo (Core)	ACH free tier, card 2.9%, wire varies	$0	SMBs paying mostly ACH
Bill.com	Per-seat	$45/user/mo (Essentials)	Check $1.69, intl wire $9.99	$0 (self-serve)	QuickBooks-anchored SMBs
Stampli	Custom (volume-based)	Reportedly ~$45/mo SMB	Bundled	~$2,000 typical	Mid-market teams wanting AI UX
Tipalti	Base + transaction	$99–$129/mo Starter	Per-payment + entity fees	$5,000–$15,000	Global payouts, 50+ countries
AvidXchange	Custom modular	~$440/mo reported	Check/virtual card surcharges	$5,000–$50,000	Real estate, construction, HOA
MineralTree	Base + transaction	$5,000/yr	Per-invoice + per-payment	Negotiated	Mid-market, ERP-deep teams
Vic.ai	Enterprise custom	~$25,000/yr (AP module)	Bundled	$5,000–$10,000	High-volume autonomous AP
SAP Concur Invoice	Per-user enterprise	~$465/mo + quote	Bundled, region-dependent	Implementation partner required	Companies already on Concur Expense

Two patterns to notice. First, the four vendors with quote-based pricing (Stampli, AvidXchange, Vic.ai, SAP Concur) account for the widest variance in actual deals — buyer reports vary by 3× on Vendr and Capterra for the same vendor at the same volume. Second, the cheapest published prices (Ramp $0, Melio $25) are real, but only if your payment mix avoids wires and cards. Add 30 international wires a month and Melio's $25 plan looks like $4,000 a year.

Vendor pricing breakdown

Ken

Ken uses a per-invoice tier model with unlimited users. Solo is $29 a month for 50 invoices, Crew is $100 a month for 500, Squad is $250 a month for unlimited. No per-seat fee, no transaction fee on payments routed through Ken, no implementation. The trade is that Ken does not run global payouts or full procurement — it handles invoice intake, extraction, approval routing, and payment queueing inside Slack. A 6-person finance team processing 500 invoices a month pays $1,200 a year. The same team on Bill.com Corporate pays $6,408 a year before transaction fees.

Ramp Bill Pay

Ramp Bill Pay is genuinely free if you use Ramp's corporate card and pay from the Ramp Business Account — standard ACH, checks, same-day ACH, domestic wires, and SWIFT are all waived. Off-Ramp-Account payments cost $0.59 per ACH and $1.99 per check effective June 2026. Ramp Plus at $15 per user per month unlocks deeper ERP integrations and advanced controls. The honest catch: Ramp's free model is a customer-acquisition play tied to card spend. If you do not use Ramp's cards, you are not the customer they built the pricing for.

Melio

Melio's Core plan is $25 a month, Boost is $55, Unlimited is $80. After the free monthly ACH allotment, additional payments are $0.50 each. Card payments cost 2.9%. International transfers and wires are priced per transaction. At 500 invoices a month with mostly ACH, the Unlimited plan at $960 a year is the right tier. Xero closed its $2.5B acquisition of Melio in mid-2025 — pricing is locked through March 2026 per the deal terms, but renewal cycles after that are an open question.

Bill.com

Bill.com (formerly Bill.com, now branded BILL) charges $45 per user per month on Essentials, $55 on Team, and $89 on Corporate. Every user is a billed seat on Essentials and Team — there is no "approver-only" rate until you hit Corporate. Checks cost $1.69, international wires cost $9.99. The math hits hard once approvers multiply: a 10-person finance team with 5 approvers and 5 AP users on Corporate runs $890 a month before a single check is cut. BILL Spend & Expense is free, but it is a card product, not invoice processing.

Stampli

Stampli does not publish pricing. Public buyer reports on G2 and Capterra cite starting figures near $45 a month for very small businesses, and quote-based pricing for everyone else. Mid-market deals at 500–1,000 invoices a month land between $8,000 and $15,000 a year per Vendr's marketplace data. Stampli's positioning is the in-context AI assistant inside the invoice approval flow — buyers consistently rate the UX above the field average, which is what the pricing premium buys.

Tipalti

Tipalti's Starter plan starts at $99–$129 a month depending on quote date. Premium and Elite are fully custom. The transaction layer is where Tipalti pricing actually gets defined: you pay a per-payment fee that varies by method (ACH, wire, PayPal, prepaid debit) and a multi-entity surcharge. Real deals for global payouts at 500 invoices a month with 30 international wires land between $25,000 and $40,000 in Year 1, including roughly $5,000 to $15,000 in implementation. Tipalti is priced for companies where international tax compliance and supplier onboarding (W-8/W-9, 1099 filing across jurisdictions) is the actual problem, not invoice count.

AvidXchange

AvidXchange uses modular custom pricing with no public tiers. Buyer reports cite base subscriptions starting around $440 a month and annualized totals between $10,000 and $13,000 for mid-market deals before implementation. Implementation runs $5,000 to $50,000 depending on ERP complexity. AvidXchange dominates verticals — real estate, construction, HOA management — where vendor-specific ERPs and check-heavy payment workflows make the per-payment surcharges easier to swallow.

MineralTree

MineralTree pricing starts at $5,000 a year for the platform and stacks per-invoice plus per-payment fees on top. Buyers on Vendr report typical mid-market deals between $15,000 and $50,000 annually. Multi-year commits (2–3 years) reportedly cut per-transaction pricing by 15–25%, and committing to a higher volume band upfront secures another 10–20% — both are levers worth using if you are confident in growth. Hidden costs (implementation, ERP integration, payment-method premiums, annual price escalators) commonly add 15–30% to the published total.

Vic.ai

Vic.ai is enterprise-priced for autonomous AP — the goal is 90%+ straight-through processing, where invoices go from receipt to approval without human touch. The AWS Marketplace listing for the AP module is $25,000 a year, and that is the floor. Real deals at scale include payment automation, GL coding autonomy, and approval automation modules, pushing Year-1 cost above $40,000 for most mid-market buyers. The math works if you are replacing two AP clerks; it does not work if invoice volume is below 500 a month.

SAP Concur Invoice

Concur Invoice does not publish pricing. The G2 floor cited by buyers is around $465 a month, and per-user pricing for mid-market deals averages near $205 per user per month in independent surveys — the highest published per-user rate in the category. Concur is rarely a standalone purchase; it is bought by companies already standardized on Concur Expense or running a broader SAP S/4HANA stack, where the procurement justification is consolidation rather than per-invoice economics.

Airbase by Paylocity, Quadient AP, and other alternatives

Worth knowing if your shortlist is still open. Airbase (acquired by Paylocity for $325M in 2024) is positioned for the 100–5,000 employee segment with custom pricing — buyer reports cite around $1,500 a month for a mid-sized test deployment. Quadient AP (formerly Beanworks) does not publish pricing; it competes on construction and real estate verticals against AvidXchange. HighRadius and Coupa sit in the upper enterprise band where AP automation is one module inside a broader treasury or procurement suite — if you are evaluating those, you are not actually buying AP software, you are buying a finance platform.

How to decode any vendor quote

When the sales rep sends a proposal, three lines determine the real cost.

Line 1: The platform fee. Ask: Is this per user, per entity, per invoice, or flat? Per-seat models compound when approver counts grow. Get the cost of adding a tenth user before you commit — it is rarely a 10× linear bump.

Line 2: The per-payment matrix. Force the rep to send a table: ACH cost, same-day ACH cost, check cost, domestic wire cost, international wire cost (with FX margin), virtual card cost, ePayables cost. Multiply by your actual monthly payment mix. This is the line that turns a $99-a-month vendor into a $40,000-a-year vendor.

Line 3: Implementation, and what counts as out-of-scope. Get implementation written down. Get a sentence about which ERP connectors are included and which are billable. Get a sentence about how custom approval flows are billed — by the hour, by the rule, or included. Mid-market buyers on Vendr report saving 20–30% on implementation by negotiating these specifics into the master agreement instead of letting them flow through SOW change orders later.

One bonus line: the annual price escalator. Most enterprise contracts have a 5–8% annual uplift baked in. Cap it at CPI or 4%, whichever is lower, in the master agreement. This is a free negotiation lever that sales reps almost always agree to.

Our recommendation

The right vendor is the one whose pricing model matches your volume curve.

Under 100 invoices a month and mostly domestic payments: Ken Solo at $29 a month, Melio Core at $25 a month, or Ramp Bill Pay free are all genuinely cheap. Pick the one that fits your existing tool stack. If your team is in Slack, pick Ken. If you already use Ramp cards, pick Ramp. If you are deep in QuickBooks Online, Melio integrates the cleanest.
100–1,000 invoices a month, growing team: Ken Crew at $100 a month flattens cost as you add approvers. Bill.com Essentials looks cheaper on paper at small team sizes but inverts above 6 users. Stampli is the right pick if AI-in-the-approval-flow UX is non-negotiable and budget allows.
1,000–5,000 invoices a month, multi-entity or international: This is Tipalti's sweet spot. Vic.ai if you have a real autonomous AP mandate from the CFO. MineralTree if your ERP is unusual and integration depth matters more than UX.
Over 5,000 invoices a month, multiple ERPs, real procurement workflows: You are buying a P2P platform, not AP software. Coupa, SAP Ariba, or Tipalti Elite — and pricing here is genuinely a single-digit-percent line on your finance budget.

Bottom line: List price is a vanity metric. Build the three-layer cost model for your actual volume and payment mix before you sign anything. The cheapest vendor at 100 invoices is rarely the cheapest at 1,000, and the cheapest at 1,000 is almost never the cheapest at 100.

FAQ

What is the cheapest AP automation software in 2026?

For domestic payments under 500 invoices a month, Ken ($100/month Crew tier), Melio (Unlimited at $80/month), and Ramp Bill Pay (free when paying from a Ramp Business Account) are the three lowest Year-1 costs. All three land under $1,500 a year. The cheapest published price (Ramp's $0) is real, but only for teams already in the Ramp ecosystem.

Why do AP automation vendors hide their pricing?

Quote-based pricing exists because per-invoice volume, payment mix, multi-entity setup, and ERP integration complexity vary 10× between buyers. Vendors selling to enterprises with $50,000-plus implementations will not anchor the conversation at a public number. The downside for buyers is that quote-based pricing makes apples-to-apples comparison nearly impossible — which is exactly why we modeled it at three volumes here.

Is per-seat pricing or per-invoice pricing better?

Per-invoice pricing wins for teams with high invoice volume and many approvers. Per-seat pricing wins for small teams with concentrated approval authority. The crossover happens at about 4–5 active users — below that, per-seat is usually cheaper; above that, per-invoice almost always wins. Per-transaction pricing (Ramp, Melio) is best when your payment mix is dominated by free or near-free methods like ACH from a connected business account.

How much does Bill.com really cost?

For a mid-market AP team with 6 users processing 500 invoices a month, Bill.com Corporate costs roughly $14,000 in Year 1 — $6,408 in seat fees plus around $8,000 in check and wire surcharges. The published $89 per user per month tells you the platform fee; the per-payment matrix tells you the rest. Add another seat and another 100 international wires and you are over $20,000.

What is the total cost of ownership for Tipalti?

Tipalti's Starter plan published at $99–$129 a month is the platform-fee floor. Real Year-1 cost for global payout at 500 invoices a month with 30+ international wires runs $25,000 to $40,000 including implementation. Multi-entity surcharges, per-payment fees, and the $5,000–$15,000 implementation are the dominant cost drivers, not the published subscription.

How do I avoid hidden fees in an AP automation contract?

Three protections. First, get the per-payment matrix in writing (ACH, same-day ACH, check, wire domestic, wire international, virtual card, ePayables). Second, negotiate implementation scope explicitly — list every ERP connector and every custom approval flow in the SOW. Third, cap the annual price escalator at CPI or 4%, whichever is lower. These three lines reduce real Year-2+ cost by 15–25% for most mid-market buyers.

AP Automation Pricing Compared (2026): What 10 Vendors Actually Cost