Channels & Attribution

Every session gets a channel when it lands, from what the browser hands over: the referring site and the parameters on the URL. The classification runs once, on the first page view, and stays with the session, which is what makes a conversion attributable to whatever actually brought the person in.

The order of checks

SnipForm works down this list and stops at the first match:

1. Your custom rules for the property. Always first, so you can override anything below.
2. Click ids: gclid, gbraid, wbraid, msclkid, fbclid, ttclid, li_fat_id, twclid, epik. A click id can only exist because an ad was clicked, so it outranks UTM tagging that a person typed.
3. Channel-first parameters: shorthand tags like ?email=welcome or ?social=launch that name the channel directly.
4. UTM parameters: utm_source and utm_medium, with common shorthands resolved (ig and instagram land in the same place).
5. Referrer domain: a visit from a site SnipForm recognises is grouped the way GA4 would group it. Unknown referrers become Site Referral.
6. Direct: nothing matched. Typed address, bookmark, or a source that sent no referrer.

Two special cases on step 5: a referrer on your own domain is Direct, not a referral, so moving between your own pages never invents a source; and OAuth redirect hosts (accounts.google.com, login.microsoftonline.com and the like) are Direct too.

Channel categories

Category	channel value	Typical medium	How it is reached
Direct	direct	(none)	No signals, self-referral, auth redirect
Organic Search	organic_search	organic	Search engine referrer, or utm_source that names one
Paid Search	paid_search	cpc	gclid/msclkid, or utm_medium in cpc, ppc, paid-search, sem
Organic Social	organic_social	social	Social referrer, or utm_medium=social, or a social utm_source
Paid Social	paid_social	cpc	ttclid/li_fat_id/twclid/epik, fbclid with paid signals, or utm_medium in paid-social, paid_social, fb, ig, an, msg
Email	email	email	Webmail referrer, or utm_medium in email, newsletter
Messaging	messaging	messaging	WhatsApp, Telegram, Messenger and similar as referrer or utm_source; utm_medium in sms, push
Video	video	video	Video platform referrer, or utm_medium in video, youtube, vimeo
Display	display	display	Google click id with a display signal, or utm_medium in display, banner, cpm, programmatic
Affiliates	affiliates	affiliate	Affiliate network referrer, or utm_medium in affiliate, partner
User Referral	user_referral	referral	user_referral={member}, or affiliate=user_referral&ref={member}
Creators	creator	influencer	creator={handle}, or affiliate=creator / affiliate=influencer with ref={handle}
Site Referral	referral	referral	Any other referrer, or a utm_source that fits nothing above

Alongside the category each session stores a readable channel name (Google Ads, Instagram, Mailchimp, Acme Blog), the method that decided it (custom_rule, click_id, utm, referrer, direct), the click id parameter if one was used, and the custom rule name if one matched.

Define your own channels

The thirteen categories above are fixed, because everything that groups, filters, compares or rolls up traffic is built on them. What is not fixed is what you call a channel and what counts as one.

Under Signals - Channels, a property can add attribution rules. A rule is a name, a category, and one or more conditions. Rules run before the built-in chain, in the order you set, and the first match wins.

The quickest shape is the ?channel= shorthand:

https://example.com/pricing?channel=staff&ref=jane&campaign=2026-Q1

Add a rule named Staff, categorised however you want it to report, with the condition Channel equals staff. Visits arriving on that link are now named Staff everywhere - the channels report, session detail, any conversion segmented by channel name - while channel_category stays one of the thirteen, so Staff still groups under bought, earned or owned and still sums correctly in any cross-property report.

A condition can test any query parameter you invent, not just the ones SnipForm knows. ?partner_code=acme-42 works as a condition field the moment you type partner_code into the rule. It can also test utm_source, utm_medium, utm_campaign, utm_content, utm_term or referrer_domain.

Every rule that pins parameters to exact values also appears in the link builder, so once a channel is named you can copy a ready-made link for it rather than reconstructing your own conditions by hand.

Why the category is not free text

It is deliberately not possible to invent a channel_category from a URL. If it were, ?channel=email would collide with the built-in, a typo would become a permanent channel, anyone holding the link could write into your primary attribution dimension, and every new built-in channel SnipForm shipped would retroactively change the meaning of somebody’s history. Naming is yours; the type stays shared, which is what keeps the numbers comparable.

Your own people are their own channels

Most attribution models fold member referrals and creator placements into Affiliates, which then mixes a self-serve affiliate link, a briefed creator and your own customer telling a friend into a single number you cannot act on. SnipForm splits them.

Each resolves two ways, so you can use whichever fits the link you are handing out:

?user_referral=jane-doe                       # direct form
?affiliate=user_referral&ref=jane-doe         # affiliate form

?creator=@somebody                            # direct form
?affiliate=creator&ref=@somebody              # affiliate form
?affiliate=influencer&ref=@somebody           # influencer is an alias for creator

Anything else on affiliate= still lands in Affiliates, so existing affiliate links keep working untouched.

fbclid is not automatically paid

Meta appends fbclid to organic shares as well as ads. A bare fbclid counts as Organic Social. It becomes Paid Social when it arrives with a paid signal: hsa_acc/hsa_net parameters from Ads Manager, a paid utm_medium (cpc, ppc, paid, paid_social), or a Meta placement medium (fb, ig, an, msg). The placement decides the name: Instagram Ads when hsa_src=ig or utm_medium=ig, else Facebook Ads.

Parameters SnipForm understands

Besides the standard five UTM parameters, these shorthands are normalised before classification:

Shorthand	Treated as
source, src	utm_source
medium, via	utm_medium
campaign, cmp	utm_campaign
email=, social=, paid=, search=, video=, affiliate=, referral=, sms=, push=, msg=	Channel-first: the key names the channel, the value becomes the channel name

?email=jane@acme.com is not a campaign tag; a value containing @ is skipped.

Source aliases are resolved to a canonical platform: fb/facebook → Facebook, ig → Instagram, tw/x → X, li → LinkedIn, tt → TikTok, yt → YouTube, ddg → DuckDuckGo, wa → WhatsApp, tg → Telegram, and so on. Unknown sources are title-cased with their TLD stripped: utm_source=acme-blog.com shows as Acme Blog.

Custom rules

Rules let you name a channel the way your business thinks about it. They run before every built-in check and are evaluated top to bottom; the first match wins, so put specific rules above general ones.

A rule is a list of conditions that must all hold, plus the category and name to assign:

Field	What it reads
utm_source, utm_medium, utm_campaign, utm_content, utm_term	The (normalised) URL parameter
referrer_domain	The referring domain, www. stripped
any other key	Any parameter on the landing URL, for tags that are not UTMs

Operators: equals, contains, starts_with, ends_with, exists, not_exists. The existence tests are the useful catch-alls: utm_source exists and referrer_domain not_exists between them separate tagged traffic from dark traffic without listing every value.

When to reach for one:

• A newsletter tool that sends no UTMs and shows up as a referral you do not recognise.
• Affiliates or partners you want counted separately rather than lumped into Site Referral.
• An internal tool or staging domain whose visits should never count as marketing.
• A platform SnipForm has not seen before, landing in Site Referral instead of Social.

Caution

Rules apply to sessions that arrive after you save them. They do not re-classify history, so a rule added today will not change last month’s numbers.

Tagging links

You do not have to remember the vocabulary. Short links carry a UTM set per link, and the link editor offers preset chips (WhatsApp, Instagram, Google Ads, Newsletter, QR Code, …) that fill utm_source and utm_medium with values the classifier is known to handle.

To see what a URL will become before you publish it, use the attribution preview: POST /v2/property/attribution/preview with the URL or its parts returns the category, name, source, medium and the method that decided it. The presets are available from the same place. See Attribution API.

In the API

Sessions are filterable by channel fields, in the query language and everywhere that accepts clauses:

channel:paid_search
channel:organic_social,organic_search
channel_name:"Instagram Ads"
channel_method:click_id
not_channel:direct

Fields: channel, channel_name, channel_method, channel_click_id, channel_custom_rule, plus utm_source, utm_medium, utm_campaign, utm_content, utm_term and referrer_domain. See the field catalog.