How-to
    Financial Management

    Set your invoice numbering and template

    Learn how to customize your invoice numbers and choose a default template to maintain consistent, professional branding.

    4 min read
    Updated June 3, 2026

    This guide explains how to set a custom invoice numbering sequence and choose a default invoice template. Consistent numbering and branding make your invoices look professional and easy to track.

    Setting a numbering system helps you and your clients reference specific invoices. Choosing a default template ensures every invoice you send has a consistent look and feel that reflects your brand.

    Before you start

    • You must have Admin or Owner permissions for your organization to access these settings.

    Set your invoice number sequence

    You can define a prefix and a starting number for all future invoices. This helps you organize invoices and can be useful for matching records in other accounting systems.

    1. Navigate to Settings → Invoices & Quotes.
    2. Find the Invoice Numbering section.
    3. In the Prefix field, enter any text you want to appear before the number. Common prefixes include INV- or the current year, like 2024-. This field is optional.
    4. In the Next Number field, enter the number you want your next created invoice to have. For example, if you want your next invoice to be number 1001, you enter 1001.
    5. Click Save Changes.
    ⚠️ Heads up: Changing the prefix or next number does not renumber existing invoices. It only affects new invoices you create from this point forward.

    Choose a default invoice template

    AtomicSam provides several templates to control the layout of your invoices. You can set a default that applies to all new invoices, but you can also override it on a case-by-case basis.

    1. Navigate to Settings → Invoices & Quotes.
    2. Scroll to the Templates section. You will see previews of the available designs.
    3. Review the options to see which best fits your business.
    TemplateBest ForKey Feature
    ClassicTraditional service businessesA clean, formal layout that clearly separates line items and totals.
    ModernCreative and tech agenciesA contemporary design with more whitespace and brand color accents.
    CompactHigh-volume or simple jobsA condensed layout that fits more information onto a single page.
    1. Select the template you want to use as the default for all new invoices. A blue border will confirm your selection.
    2. Your choice is saved automatically.
    💡 Tip: When you create or edit an invoice, you can choose a different template from the Template dropdown before you send it.

    Good to know

    • Invoice numbers must be unique within your organization. AtomicSam prevents you from saving an invoice with a duplicate number.
    • You can edit the invoice number on any Draft invoice. Once an invoice has been sent or has a payment recorded against it, the number is locked to protect your financial records.
    • If you connect to an accounting integration like Xero or QuickBooks Online, your invoice numbering may be controlled by that system instead. Check your settings in Settings → Integrations to confirm.
    • The logo and business address that appear on your invoices are managed in Settings → Organization Details.

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