How Harvest creates invoice IDs

When you create a new invoice in Harvest, Harvest will suggest a new invoice ID based on the other IDs that have come before it. The suggested invoice ID can be edited during invoice creation or left as suggested. Once an invoice has been saved, the invoice ID cannot be used by any other invoice.

By default, Harvest invoice IDs start at 1 and then auto-increment upward on each subsequent invoice. For example, if you’ve created ten invoices in Harvest, the default invoice IDs will be 1 through 10.

We don’t backfill for missing IDs, unless the invoice with the largest ID (usually the most recent invoice) is deleted. For example, if you have ten invoices and delete invoice #6, the next invoice created will not have an ID of 6 to backfill for the missing number—instead, it’ll have an ID of 11. On the other hand, if you delete invoice #10, the next invoice created will have an ID of 10.

How to edit an invoice ID

If you'd prefer to use a different invoice ID number than the one automatically suggested, you can edit the ID by clicking into the Invoice ID field and typing your preferred invoice ID. As long as the invoice ID you use is the largest ID in the account and you're using an account-wide invoice ID pattern, the next invoice you generate will have a suggested invoice ID that follows the new sequence. 

For example, if the existing invoices in your account have IDs of 1 through 10 , and you edit your next invoice ID to 500 , the following invoice will have the ID 501 .

How to use invoice ID codes

Invoice ID codes can be used to create either client-specific or account-wide series of invoice IDs. 

By default, each invoice ID series is specific to the associated client in your account. If you want your invoices to be numbered as one cohesive sequence across all clients in your account, you'll need to manually add a universal invoice ID code to one invoice for each client. This will kick off a seamless invoice ID sequence across all your account's invoices.

For example, if you want all invoices to use the code INV-before the invoice number, you'll need to manually add INV- to one invoice for each client. After that, Harvest will automatically use INV-for every invoice you create.

Note that the first-ever invoice you create for a client will default to the next-largest invoice ID in the account, which may include a specific client code.

Including the current year

If you’d like to have the current year included in your invoice IDs, you can prepend 2024- to your invoice ID. On January 1, 2025, Harvest knows to change to 2025- and start over from 1.

For example, if your final invoices of the year are 2024-105, 2024-106, and 2024-107, then the first invoice of 2025 will have a suggested invoice ID of 2025-001.

Note that this coding sequence will be specific to any clients you implement it with. If you'd like to include the current year on all invoices in your account, you'll want to add the year code to an invoice for each client. You'll also need to ensure that an invoice is created for every client each year, even if it's only a draft that's not sent to your client, in order to keep the sequence active for them. From there, Harvest will recognize it as an account-wide year code sequence instead of a client-specific sequence.

Including a client code

It’s possible to include a client code in the invoice ID in order to make the series of IDs unique to a client. You can do that by prepending the client code and a hyphen to the invoice ID.

For example, for two clients (ABC Company and DEF Design), you can create two invoice ID series with ABC-1001 and DEF-1001, respectively. Harvest will recognize that those are client-specific ID sequences and increment them separately when a new invoice is created for either company.

Note that Harvest will recognize any code you use (including INV- or 2024-) as unique to that client unless you add it to an invoice for each client within your account.

Including both the current year and the client code

This can also be done, but in order for Harvest to correctly increment the invoices, you’ll need to format them as YEAR-CLIENT-INVOICE.

For example, 2024-ABC-1001 and 2024-DEF-1001 will create two distinct series of invoice IDs that increment separately by both calendar year and client ID. On January 1, 2025, the available invoice IDs would be 2025-ABC-0001 and 2025-DEF-0001, respectively.