Choosing a POS merchant service means finding a payment processing solution that works with your point-of-sale (POS) system, not just picking software to ring up sales. Your choice affects processing fees, how quickly you receive funds, how you handle refunds, and how easily you reconcile transactions with your sales records. The right setup can simplify daily operations and give you better visibility into what your business earns and pays in processing costs.
The best POS merchant services combine reliable payment processing with POS tools that fit your business model. I compared providers based on pricing and contract terms, payment and POS integration, processor flexibility, operational features, reliability, security, and support. The six options below serve different needs, from small businesses looking for a straightforward all-in-one system to retailers that need advanced inventory management or the freedom to choose their payment processor.
| Best for | Starting monthly cost | |
|---|---|---|
| Helcim | Businesses seeking transparent, interchange-plus processing | $0 |
| Square | Small businesses wanting an easy-to-use, all-in-one POS | $0 |
| KORONA POS | Retailers wanting flexibility to choose their payment processor | $59 |
| Shopify POS | Retailers selling online and in person | $39 |
| Lightspeed Retail | Retailers with complex inventory and multi-location needs | $89 |
| Toast | Restaurants needing integrated POS and restaurant management tools | $0 |
Learn more:
- What is a POS System? Overview, Meaning & Best Practices
- How to Use a POS System: Step-by-Step Guide for Businesses
- What Are the Different Types of POS Systems?
Best POS merchant services compared
My rating (out of 5) | Payment processing model | POS and payment integrations | Processor flexibility | |
|---|---|---|---|---|
| Helcim | 4.15 | Interchange-plus pricing | Payment processing with POS tools and transaction reporting | Helcim only |
| Square | 4.12 | Flat-rate pricing | Sales, payments, and inventory connected in one system | Square only |
| KORONA POS | 4.11 | Rates set by the merchant's chosen processor | Connects checkout transactions with inventory and sales reporting | Processor-agnostic; merchants can choose from compatible third-party payment processors. |
| Shopify POS | 4.04 | Flat-rate pricing with Shopify Payments | Syncs in-person and online orders, inventory, and sales | Third-party payment options for online checkout; Shopify Payments only for in-person payments |
| Lightspeed Retail | 3.76 | Rates depend on the processing option and plan | Connects payments with sales reporting and retail inventory tools | Supports selected third-party processors, but availability and fees depend on region, plan, and supported processors |
| Toast | 3.68 | Custom processing rates | Payments connect with restaurant ordering and operational workflows | Toast only |
Why you can trust my advice
I have more than five years of experience researching and evaluating small business software, including payment processing, POS systems, accounting platforms, and workflow tools. My focus is helping business owners understand their options and choose technology that fits their budget, payment needs, and day-to-day operations.
For this guide, I compared POS merchant services based on their processing costs, POS and payment integrations, processor flexibility, business operations features, and reliability and support. I reviewed published pricing, processing terms, product documentation, and integration details to identify each provider's strengths, limitations, and best-fit use cases.
Methodology: How I evaluated the best merchant POS services
When evaluating the best POS merchant services, I focused on how well each provider combines payment processing with the POS tools businesses use to manage sales. I considered the cost of accepting payments, how transactions connect with sales records and inventory, and whether merchants can choose their own payment processor. These factors help distinguish a complete POS merchant service from a POS system that primarily handles checkout or a payment processor with limited operational tools.
I evaluated providers using five weighted criteria:
- Payment processing costs and contract value (25%): I compared processing rates, monthly fees, hardware costs, contract terms, cancellation fees, and overall value.
- POS and payment integration (25%): I assessed how well each system connects transactions with sales records, refunds, reconciliation, reporting, and online or in-person sales channels.
- Payment flexibility and merchant account control (20%): I considered accepted payment methods, processor choice, settlement options, account portability, and transaction restrictions.
- Business operations and scalability (15%): I evaluated checkout workflows, inventory and order management, multi-location support, and integrations with accounting and other business tools.
- Reliability, security, and support (15%): I reviewed payment reliability, security measures, fraud and chargeback tools, funding issue resolution, and customer support.
I scored each provider on a five-point scale and calculated its overall rating using the weighted criteria. I also reviewed vendor pricing pages and product documentation to verify key features, fees, processing requirements, and limitations. The ratings reflect how well each provider meets the needs of businesses looking for a combined POS and payment processing solution, rather than how many features its software offers.
Helcim: Best for transparent interchange-plus pricing
Pros
- No monthly software fees, long-term contracts, or cancellation fees
- Interchange-plus pricing with automatic volume discounts
- POS, invoicing, payment links, and accounting tools in one platform
Cons
- Total processing costs vary by card and transaction type
- In-person payments require compatible hardware
- Recurring payments carry an additional 0.4% fee per applicable transaction
Why I chose Helcim
Helcim's pricing is worth a closer look if your business processes a steady stream of card payments. Instead of charging the same percentage for every card transaction, Helcim passes through interchange and network fees and adds its own markup. It also lowers that markup as your monthly processing volume increases. This can make Helcim less expensive than a flat-rate provider for some businesses, though the savings depend on your transaction mix and total volume.
The POS software is free, and Helcim includes tools for managing sales, inventory, customers, and payment reporting. You can also send invoices, collect ACH payments, and create payment links, which is useful if you take deposits or bill clients remotely. The catch is that you still need to account for hardware costs and variable processing fees. And if you want to keep your existing POS while switching to a different payment processor, Helcim isn't the most flexible choice.
Pricing and standout features
| Monthly software fee | $0, including POS software |
| In-person card processing | Interchange + 0.40% + $0.08 per transaction for monthly card volume up to $50,000 |
| Online and invoice payments | Interchange + 0.50% + $0.25 per transaction for monthly card volume up to $50,000 |
| ACH bank payments via invoice | 0.5% + $0.25 per approved transaction below $25,000, capped at $6 |
| Hardware |
|
| Recurring payments | Additional 0.4% per applicable transaction |
| Processor flexibility | Helcim processing required for payments through Helcim POS |
| Payouts | Next-business-morning deposits for card transactions |
| Customer support | Phone, email, and in-account support options |
| Standout features |
|
Who should use Helcim
Helcim is a good fit for businesses that:
- Process enough card payments to benefit from interchange-plus pricing and volume-based discounts.
- Want POS software without another monthly subscription.
- Need in-person payments alongside invoicing, payment links, and ACH transfers.
- Prefer transparent pricing and no long-term contracts.
Helcim may be less suitable for businesses that need a broad retail POS ecosystem with advanced multi-location management or want to choose their own payment processor. Its interchange-plus model can also make transaction costs less predictable than flat-rate pricing, particularly for businesses with low or inconsistent sales volume.
Square: Best overall for small business
Pros
- Free POS plan with no monthly software fee
- Published processing rates and no long-term contracts
- Integrated sales, inventory, and reporting tools
Cons
- Integrated card processing requires Square
- Online and manually entered payments cost more than standard in-person transactions
- Some advanced features require a paid plan
Why I chose Square
Square is a strong choice for small retailers, service businesses, and other merchants that want payments and everyday sales operations in one place. Its free plan includes POS software, inventory tools, sales reports, customer records, and an online store that syncs with in-person sales. Merchants can also accept contactless payments using compatible phones, reducing the need to buy dedicated hardware upfront.
Its flat-rate pricing is easy to understand, but the rate depends on how you accept payment. The free plan charges 2.6% plus $0.15 for in-person tap, dip, or swipe transactions, 3.3% plus $0.30 for online or invoice payments, and 3.5% plus $0.15 for manually entered payments or cards on file. Square doesn't charge a monthly fee for its Free plan, but businesses with high transaction volumes should compare the total cost against interchange-plus alternatives.
Pricing and standout features
| Monthly software fee | $0 for Free; paid plans available |
| In-person card processing | 2.6% + $0.15 per transaction on Free |
| Online and invoice payments | 3.3% + $0.30 per transaction on Free |
| Manually entered payments or card on file | 3.5% + $0.15 per transaction |
| ACH bank payments via invoice | 1%, with a $1 minimum |
| Hardware |
|
| Processor flexibility | Square processing required for integrated card payments |
| Payouts | Standard next-business-day transfers; instant transfer options may be available for a fee |
| POS and payment integrations | Sales, inventory, online orders, and payment reporting connected within Square |
| Standout features |
|
Who should use Square
Square is a good fit for businesses that:
- Want to start accepting in-person payments without a monthly POS software subscription.
- Need basic inventory, sales reporting, and online selling in one system.
- Prefer published flat-rate processing fees over interchange-plus pricing.
- Want a straightforward checkout setup with the option to add hardware as the business grows.
It may be less suitable for high-volume merchants who could negotiate lower processing costs elsewhere, or for businesses that want to choose their own payment processor.
Related:
KORONA POS: Best for businesses that want to choose their payment processor
Pros
- Choose your own payment processor
- No forced long-term contracts
- Inventory tools and multi-location features on higher tiers
- 24/7 in-house support
Cons
- Processing fees are separate from the software subscription
- Hardware costs vary by setup
- Advanced features and industry modules cost extra
Why I chose KORONA POS
KORONA's biggest advantage is that changing payment processors doesn't have to mean replacing your POS system. The company says its software integrates with a range of processors through supported payment terminals and integrations. That can give merchants room to negotiate rates or move to another provider if their processing costs or service deteriorate. Check compatibility with your preferred processor before signing up, since the setup still depends on supported integrations.
Its software is built for more than basic checkout. The Core plan covers registers, product records, sales reports, gift cards, and API access. The Retail tier adds inventory counts, real-time stock tracking, barcode automation, and supplier ordering, while Plus adds deeper inventory analysis and multi-location reporting. These tools can help specialty retailers, convenience stores, and other inventory-heavy businesses manage daily operations without giving up processor choice.
Pricing and standout features
| Core plan | $59 per terminal per month |
| Retail plan | $79 per terminal per month |
| Plus plan | $99 per terminal per month |
| Payment processing | Set by your chosen processor; not included in the software subscription |
| Hardware | Costs vary by equipment and configuration; compatible existing hardware may be usable |
| Processor flexibility | Selected third-party processors may be supported, depending on product version and region; additional fees may apply |
| Contract terms | Month-to-month subscription with no forced contract; annual plans may be discounted |
| Inventory and reporting | Stock tracking and automation on Retail; advanced inventory analysis and multi-location tools on Plus |
| Customer support | 24/7 chat and phone support listed on the U.S. pricing page |
| Optional modules | Industry-specific features for food service, invoicing, ticketing, franchising, and custom integrations |
| Standout features |
|
Who should use KORONA POS
KORONA POS is worth considering if you:
- Want to negotiate processing rates or retain a compatible merchant services provider.
- Run a specialty retail, convenience, or ticketing business with specific operational needs.
- Need inventory controls or reporting across multiple locations.
- Prefer a monthly software subscription without a forced long-term contract.
It may be less convenient if you want one provider to bundle POS software, hardware, and payment processing into a single arrangement. You'll need to evaluate the processor's rates, account terms, and hardware compatibility separately, then add those costs to KORONA's per-terminal subscription to estimate your total expense.
Shopify POS: Best for retailers selling online and in person
Pros
- Syncs online and in-store orders and inventory
- Centralizes customer records and sales reporting
- Supports multiple locations and sales channels
Cons
- Requires a paid Shopify subscription
- POS Pro costs extra for advanced retail features
- Third-party online payment providers incur additional Shopify transaction fees
Why I chose Shopify POS
Shopify POS is most useful when a retailer needs its physical and online stores to work as one business. A customer might order an item online, exchange it in person, or buy something in-store that needs to be shipped later. Shopify's shared order and inventory records help staff handle those transactions without maintaining separate systems for each sales channel. Retailers can also manage customer information and review sales activity from the same back office.
Payment processing is where the costs need a closer look. On Shopify's U.S. Basic plan, online card rates start at 2.9% plus $0.30, and in-person rates start at 2.6% plus $0.10. If you use a third-party payment provider for online transactions, Shopify charges an additional 2% transaction fee on Basic, on top of the provider's processing fees. You can use an external terminal for in-person payments, but those transactions may require separate payment tracking rather than the same integrated workflow as Shopify Payments.
Pricing and standout features
| Monthly software fee | Basic starts at $39/month |
| Online card processing | Starts at 2.9% + $0.30 per transaction on Basic |
| In-person card processing | Starts at 2.6% + $0.10 per transaction on Basic |
| Third-party online payment providers | Additional 2% transaction fee on Basic, plus the provider's fees |
| POS Pro | Additional $89/month per location |
| Hardware | Compatible card reader and a smartphone or tablet required; other hardware costs extra |
| Processor flexibility | Third-party providers are available for online checkout; in-person processing options depend on country and setup |
| POS and payment integrations | Syncs online and in-person orders, inventory, customer records, and sales reporting |
| Standout features |
|
Who should use Shopify POS
Shopify POS is a good fit for retailers that:
- Already run an online store on Shopify and want to add in-person sales.
- Sell through several channels and need shared inventory and order records.
- Plan to expand into physical locations while keeping their ecommerce operations centralized.
- Want retail hardware and software that connect to their existing Shopify setup.
It may be less appealing to a brick-and-mortar business that doesn't need ecommerce, or to a merchant whose priority is choosing its own payment processor and minimizing subscription costs. Compare the monthly Shopify plan, processing rates, third-party transaction fees, and any POS Pro charges before committing.
Related:
- Shopify Review 2026: Pricing, Features, and Who It’s Best For
- Square vs Shopify: Which POS Is Best for You?
Lightspeed Retail: Best for retailers with complex inventory needs
Pros
- Detailed inventory and product-variant management
- Sales, staff, and inventory reporting
- Integrations for accounting, ecommerce, and marketing
Cons
- Higher monthly cost than many entry-level POS systems
- Processor choice can depend on the product version and region
- Additional processing or service fees may apply
Why I chose Lightspeed Retail
Lightspeed stands out when inventory management is central to the business. Retailers can track products and variants, manage stock across channels, and use sales and inventory reports to make purchasing decisions. Its higher-tier plans add capabilities such as more advanced reporting, loyalty tools, and inventory insights, which can be useful for growing stores with more complicated operations.
The main consideration is whether those tools justify the subscription and payment costs. Lightspeed's U.S. Retail X-Series pricing lists Basic at $89 per month, Core at $149, and Plus at $289, with one register included in each plan. The pricing page also lists an in-person Lightspeed Payments rate of 2.6% plus $0.10 per transaction, but rates and fees may vary by business and agreement. If keeping your existing processor is a priority, confirm any third-party processing fees and compatibility restrictions before signing up.
Pricing and standout features
| Basic plan | $89/month |
| Core plan | $149/month |
| Plus plan | $289/month |
| In-person processing | Lightspeed Payments lists 2.6% + $0.10 per transaction on the U.S. pricing page |
| Hardware | Compatible terminals, scanners, and other equipment; costs depend on the setup |
| Processor flexibility | Selected third-party processors may be supported, depending on product version and region; additional fees may apply |
| Inventory management | Product and variant tracking, stock management, and purchasing tools |
| Reporting & integrations | Sales, staff, and inventory reporting, plus accounting, ecommerce, and marketing integrations |
| Customer support | 24/7 chat and phone support listed on the U.S. pricing page |
| Standout features |
|
Who should use Lightspeed Retail
Lightspeed Retail is worth considering if you:
- Manage a large catalog or many product variants.
- Need detailed inventory and purchasing workflows.
- Operate across multiple sales channels or are preparing to expand.
- Want sales and inventory reporting that goes beyond basic daily totals.
A smaller store with straightforward checkout needs may find a simpler, lower-cost POS more practical. And if you want to retain your current payment processor, verify compatibility and any additional fees for your specific Lightspeed product and location before committing.
Related: Lightspeed vs Shopify: Which POS is better in 2026?
Toast: Best for restaurants that need integrated payments and operations
Pros
- Connects payments with orders, tips, and restaurant workflows
- Restaurant-focused hardware and checkout tools
- Optional online ordering, inventory, and team management features
Cons
- Integrated card payments run through Toast
- Processing rates depend on the plan and agreement
- Hardware, add-ons, and additional terminals can increase costs
Why I chose Toast
Toast's strength is how closely its payment tools fit restaurant service. Staff can manage checks, tips, and payments through the same system used to handle orders, while handheld devices let servers take orders and payments at the table. Restaurants can choose a countertop setup for a fixed checkout station, a Wi-Fi handheld for tableside service, or a cellular kit for mobile operations such as food trucks and off-site events.
The Starter Kit pricing needs a closer look than the advertised $0 monthly starting price suggests. Toast offers pay-as-you-go and traditional pricing arrangements, with different combinations of hardware costs, software fees, and processing rates. The pay-as-you-go option can reduce upfront expenses for eligible restaurants, but the processing rate may be higher than under a traditional agreement. Since Toast also requires its own processing for integrated card payments, ask for a quote based on your expected card volume and review the agreement before committing.
Pricing and standout features
| Monthly software fee | Starter Kit advertised from $0/month for eligible restaurants; standard POS plan advertised from $69/month |
| Payment processing | Rates depend on the pricing arrangement and merchant agreement |
| Hardware options | Countertop, Wi-Fi handheld, and cellular Starter Kits |
| Additional equipment | Extra terminals and peripherals may cost more |
| Processor flexibility | Toast processing required for integrated card payments |
| POS and payment integrations | Connects restaurant orders, checks, tips, payments, and sales reporting |
| Optional tools | Online ordering, delivery integrations, inventory, payroll, and other restaurant management features, depending on product selection |
| Standout features |
|
Who should use Toast
Toast is a good fit for restaurants that:
- Need payment processing connected to table service, counter service, or kitchen workflows.
- Want to take orders and payments at the table or in mobile settings.
- Prefer restaurant-specific hardware over a general-purpose retail POS.
- Want to add online ordering and restaurant management tools to the same platform.
Toast may be less suitable for retailers or service businesses that don't need restaurant features, or for merchants who want to choose their own payment processor. Before signing up, compare the processing rates, hardware arrangement, software fees, and contract terms. The lowest advertised monthly price doesn't necessarily mean the lowest overall cost.
Related: Toast vs Square: Best Restaurant POS System
How to choose the best POS merchant service for your business
Start with how your business accepts payments and what you need your POS system to manage. A provider with the lowest advertised processing rate may not be the least expensive once you account for monthly software, hardware, add-on features, and contract terms.
Consider these factors before choosing a POS merchant service:
- Compare total processing costs. Look beyond the advertised rate. Calculate processing fees alongside monthly subscriptions, per-transaction charges, hardware, chargeback fees, and any additional fees for using a third-party processor.
- Match the POS tools to your workflow. A small service business may need simple checkout, invoicing, and reporting. A retailer may need inventory and purchase-order management, while a restaurant may need table management, tipping, and kitchen workflows.
- Check processor restrictions. All-in-one systems can simplify setup, but some require you to use their payment processing. If you want to negotiate rates or keep your existing merchant account, confirm that the POS supports your processor and check for additional fees.
- Review payout timing and payment methods. Confirm when card sales reach your bank account, whether faster transfers cost extra, and whether the provider supports the payment methods your customers use.
- Verify hardware and integration costs. Check whether your existing terminals, card readers, barcode scanners, and accounting software are compatible. Ask whether you need separate subscriptions or paid integrations.
- Read the contract before signing. Review minimum processing requirements, cancellation fees, equipment obligations, and renewal terms. A low introductory price may not reflect your long-term costs.
Before committing, estimate your monthly costs using your typical transaction volume and average sale amount. If you're comparing interchange-plus and flat-rate pricing, request a quote based on your actual payment mix. That gives you a more useful comparison than processing rates alone.
FAQs
What is a POS merchant service?
A POS merchant service combines payment processing with a point-of-sale system that records sales and supports checkout operations. Depending on the provider, it may also include inventory management, sales reporting, customer records, and online payment tools.
What is the difference between a POS system and a merchant service?
A POS system manages checkout and sales operations, while a merchant service enables a business to accept and process electronic payments. Some providers bundle both into one platform, while others let you connect POS software to a separate payment processor.
Which POS merchant service has the lowest fees?
There is no single lowest-cost option for every business. Square uses flat-rate pricing, Helcim uses interchange-plus pricing with volume-based discounts, and KORONA POS lets merchants choose a compatible processor. Compare processing rates, monthly fees, hardware, and other charges using your typical transaction volume before deciding.
Can I use my own payment processor with a POS system?
Yes, but it depends on the POS provider. KORONA POS supports compatible third-party processors, and Lightspeed supports selected processors depending on the product and region. Square, Helcim, Toast, and Shopify Payments have more restrictions for integrated card processing, so check the specific setup and any additional fees before signing up.
Do POS merchant services require a monthly fee?
Not always. Square and Helcim offer free POS merchant services, while Shopify POS requires a paid Shopify subscription. Toast advertises eligible Starter Kits from $0 per month, and Lightspeed Retail and KORONA POS offer paid subscription plans. Processing fees and hardware costs may still apply even when software is free.
How do I choose the best POS merchant service for my business?
Compare total payment processing costs, POS features, supported payment methods, payout timing, hardware compatibility, and contract terms. Then narrow your options based on your workflow. For example, restaurants may prefer Toast, retailers selling online and in person may benefit from Shopify POS, and businesses that want processor flexibility can consider KORONA POS.
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