Best Payment Processors for Small Business
Quick answer: For businesses under $5K/month, Square is the easiest to start. For businesses over $5K/month, a dedicated merchant account with interchange-plus pricing saves 15-40% on processing fees. For high-risk businesses, Unison Payment Solutions provides stable processing where aggregators (Stripe, Square, PayPal) won't.
Choosing a payment processor is one of the most impactful financial decisions a small business makes. The wrong choice can cost you thousands per year in excess fees, put your revenue at risk through account holds, or limit your growth by restricting your business model.
Payment Processor Types
Aggregators (Square, Stripe, PayPal)
- Pros: Instant signup, no underwriting, simple pricing
- Cons: Higher rates, account instability, no dedicated support, product restrictions
- Best for: New businesses under $5K/month with no high-risk products
Dedicated merchant accounts (Unison, etc.)
- Pros: Lower rates (interchange-plus), account stability, dedicated support, high-risk support
- Cons: 3-10 day approval, more documentation required
- Best for: Established businesses over $5K/month, any high-risk business
Top Processors Compared
| Processor | Pricing | Best For | High-Risk |
|---|---|---|---|
| [Unison Payment Solutions](/contact) | Interchange-plus | Growing and high-risk businesses | Yes |
| Square | 2.6% + $0.10 | Small retail/services | No |
| Stripe | 2.9% + $0.30 | Online startups | No |
| PayPal | 2.99% + $0.49 | Casual/marketplace sellers | No |
How to Choose
Step 1: What do you sell?
If your product or service is in a high-risk category — firearms, CBD, vape, supplements, adult, gambling, travel, etc. — your only option is a dedicated high-risk merchant account. Aggregators will eventually shut you down.
Step 2: How much do you process?
- Under $3K/month: Square or PayPal
- $3K-10K/month: Start considering interchange-plus
- Over $10K/month: Interchange-plus saves significant money
- Over $50K/month: Interchange-plus is essential
Step 3: In-person, online, or both?
- In-person only: Clover POS or PAX terminal with interchange-plus
- Online only: Payment gateway with your eCommerce platform
- Both: Single merchant account covering card-present and card-not-present
Step 4: What features do you need?
- ACH/bank transfers — for invoicing, B2B, high-ticket
- Customer financing — for high-ticket products/services
- Chargeback prevention — for high-risk and subscription businesses
- Cash discount program — to offset processing fees
- Invoicing — for service businesses and B2B
The Real Cost of Cheap Processing
Free card readers and zero monthly fees sound appealing, but consider:
- Square's flat 2.6% on a $500 debit card transaction costs $13.10 — interchange-plus costs $3-5
- PayPal can hold your funds for weeks with no explanation
- Stripe terminates accounts for product categories you didn't know were restricted
The cheapest processor is not the one with the lowest listed rate — it is the one that gives you the lowest effective rate on your actual transaction mix.
Contact Unison for a free rate analysis.