Zoho CRM email templates: why merge fields come out blank or wrong, and what to check

What Zoho says a template is tied to

Per Zoho's Email Templates help page, a template belongs to one module: a lead template only appears when you email leads. It says lead templates should not include contact-related fields, and the reverse. To reuse a template in another module, Zoho says to clone it and update the merge fields (such as name and company details) to match the new module.

Zoho's developer guide for templates says the same from the other direction: each template is tied to one record type, chosen when you create the template.

Source: Zoho Help: Email Templates, Zoho Help: Email and Inventory Templates (developer guide)

Insert fields from the list, do not type them

The developer guide describes inserting a field by choosing a module under Available Merge fields, picking a field from the User, Organization or Specific Module category, using Copy Merge Field value and pasting it into the body. Its example is $contacts_firstname.

Zoho's pages show more than one syntax. The help page's sample uses the form ${Leads.First Name} and ${User.First Name}, while the developer guide's email example uses the $leads_firstname style and its inventory-template example uses ${User.First Name}. The developer guide does not explain why they differ. Advice: copy fields from the picker in your own org rather than typing them from memory or from a blog.

Source: Zoho Help: Email Templates, Zoho Help: Email and Inventory Templates (developer guide)

Blank field checklist (advice)

• Is the template's module the same as the record you are sending to? A template for the wrong module either will not be offered or will pull the wrong fields.
• Does the field have a value on that record? The Zoho pages we read do not describe a fallback value for an empty field in CRM email templates, so assume an empty field renders as empty.
• Is the field on a related record, for example an Account field in a Contact template? A Zoho community thread we read reports exactly this: custom Account fields were available only when the template was set to Accounts, and after switching the template to Contacts those merge fields came out blank. That thread has no Zoho reply, so treat it as a user report, not a documented rule, and test it in your own org.
• Re-insert the field from the picker instead of editing the tag text.
• Send a real test to a record you control that has the fields filled in, rather than relying on a preview alone.

Source: Zoho Community: Email template merge fields (user thread, no Zoho reply)

Limits and where templates are used

Zoho's Email Templates help page lists a maximum template length of 200,000 characters, attachments of up to 10 files with a combined 3MB limit, a template name of up to 75 characters, and a subject of up to 150 characters. Zoho's separate developer guide gives 3MB for an attachment and 64,000 characters for the email body. These pages disagree on body length, so check the limit in your own org before relying on either figure.

The help page lists places a template can be used, including Send Mail, Mass Email, Schedule Mass Email, auto-responders, macros, workflow automation, approval processes, case escalation, web forms, auto-response rules, wizards, Blueprint and CommandCenter. It says a template linked to a workflow, case escalation, macro or similar function cannot be deleted until those links are removed. The page is inconsistent on how many features that is (it says both thirteen and ten), so treat the list as indicative.

Source: Zoho Help: Email Templates, Zoho Help: Email and Inventory Templates (developer guide)

Do not confuse email templates with mail merge

Zoho's Mail Merge Templates are a different feature, built in Zoho Writer to generate letters, forms, labels and agreements in bulk, and optionally email them. Zoho states they are available in the Standard, Professional, Enterprise and Ultimate editions and lists separate limits: up to 10 fields from a subform, up to 3 dynamic tables per template, only the first 100 related-list items fetched, a default of 1000 merges a month per organisation on Professional, Enterprise and Ultimate, a daily cap of 1000 merges, and a maximum of 1000 mail merge emails per CRM organisation per day. Zoho also says templates cannot currently be deployed from sandbox to production.

If a team says merge fields are failing in a letter run, work out first which of the two features they mean, because the limits and troubleshooting differ.

Source: Zoho Help: Mail Merge Templates

When to bring in help

If many templates were copied between modules, or workflows and Blueprints send emails using templates nobody owns, a tidy-up usually means auditing templates, the automations that use them and the fields they depend on together. Skyfall Labs does this within Zoho CRM customization. As an official Zoho Partner we have a commercial interest, so treat our view accordingly.