The most common billing mistake digital marketing agencies make is mixing client ad spend into their own service fee — which breaks the GST calculation. Here’s the correct bill format and how BizKhata keeps ad spend and your fee cleanly separated.
Digital marketing agency billing software has to separate two fundamentally different amounts on the same invoice: your own billable service (SEO, social media, PPC management fee) and the client’s ad spend that you’re passing through to Google, Meta or another platform on their behalf. Mixing the two into one line item overstates your taxable revenue and gets the GST calculation wrong.
On top of that, most agency work is billed monthly, across multiple platforms and services at once — SEO, SMM, Google Ads and Meta Ads can all appear on the same client’s invoice for the same billing period, each needing its own platform tag.
| Field | Why It’s Needed |
|---|---|
| Invoice number & date | Standard GST requirement, sequential for the financial year |
| Campaign / Project Name | Ties every line item back to the specific engagement |
| Platform | Google Ads, Meta, LinkedIn, YouTube, SEO, Email, etc. |
| Billing Period | Month/year the invoice covers, since most billing is recurring |
| Ad Spend / Budget | Client’s ad budget, shown separately from your service fee |
| Deliverables | What was delivered for that period — posts, reports, campaigns |
| SAC code & GST rate | 998361 at 18% on your fee; ad spend pass-through at 0% |
| Total invoice value | Final payable amount, fee and ad spend clearly split |
Below is BizKhata’s template gallery — the Digital Marketing Agency template sits alongside 35+ other GST-ready formats, pre-configured with platform, billing period and ad-spend fields so you’re not building the invoice structure from scratch.

BizKhata’s Digital Marketing Agency template, ready to apply with one click
A dedicated 0% GST pass-through line keeps client ad budgets out of your taxable service fee.
SEO, SMM, Google Ads, Meta Ads and more, each tagged by platform on the same invoice.
Monthly billing period fields built for recurring retainer clients.
SEO, content, web development, influencer coordination and reporting, pre-loaded with market rates.
Billing continues even if the internet connection drops.
No recurring subscription — pay once for a billing system built for agency retainers.
BizKhata includes GST-ready templates for other service businesses too — explore the ones closest to yours:
No. GST applies to your service/management fee, not to the client’s ad budget itself. Ad spend passed through to Google or Meta should be its own line item, billed at actuals with no markup and no GST, kept separate from your taxable service fee.
SEO, social media management, PPC management fees, content and web development services are taxed at 18% GST under SAC 998361. The ad spend pass-through portion is not a taxable service and should be shown separately.
A monthly retainer should be billed as a fixed recurring line item for the bundle of services agreed (SEO, SMM, PPC management), with the billing period clearly stated, separate from any ad spend pass-through for that month.
Campaign or project name, platform (Google Ads, Meta, LinkedIn, etc.), billing period, ad spend/budget amount, and a list of deliverables for that period, alongside the standard invoice number, date and GST breakdown.
Yes. A single monthly invoice commonly includes SEO, social media management, Google Ads fee, Meta Ads fee and reporting as separate line items, each tagged with the relevant platform.
Yes. BizKhata’s Digital Marketing Agency template includes SEO, SMM, PPC, content, web and retainer line items pre-loaded, plus a dedicated 0% GST ad-spend pass-through line so client budgets never mix into your taxable fee.
Download BizKhata free for Windows or Mac — retainer billing, ad-spend pass-through, GSTR-ready.
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