(And if you need more than 1,000 invoices, you can contact Zoho directly to discuss a custom invoicing plan.) You can send invoices to an unlimited number of clients, and while Zoho does have an invoice limit, it’s 1,000 invoices a year-more than enough for most freelancers, solopreneurs, and small to midsize businesses. Zoho Invoice’s completely free invoicing software includes customizable invoices with professional templates.