Using Mailing Lists Effectively

How TIPS models a Mailing List

A Mailing List in TIPS is just metadata — a name and a description. The actual addresses live on Traveler Profiles, and the list-to-Traveler relationship is a separate membership table. Two consequences fall out of that:

• An email address can be on multiple lists. Each Traveler Profile is unique per (Client, email), but a Traveler can belong to as many of your lists as makes sense. That's the whole point: a person who rides Route 47 and lives downtown can be on both the "Route 47 riders" list and the "Downtown residents" list.
• List metadata is cheap; Travelers are durable. Deleting a list doesn't necessarily delete the people who were on it. If a Traveler has responses on file, their profile is preserved so your analytics history stays intact.

Segment by intent, not by size

The biggest single decision you'll make is how to slice your audience. The wrong instinct — common among first-time users — is "one big list of everyone, filter later." The right instinct is smaller, intent-named lists that mean something at a glance.

Compare two strategies:

There is no per-list cost in TIPS — you can have dozens. Some naming patterns that work well:

• By route or corridor. "Route 47 riders", "Light-rail Phase II stakeholders".
• By relationship. "City staff", "Transit board", "Public-meeting attendees, March 2026".
• By engagement history. "Spring 2026 grant survey respondents", "Demo-day signups".
• By geography. "Downtown residents", "North-county employers".

Cross-list overlap: handled automatically

You'll often want to send a survey to several lists at once — "Downtown residents" plus "Route 47 riders" for a corridor-improvement survey, for example. TIPS recognizes the overlap and sends exactly one invitation to anyone who appears on more than one selected list.

The Send Invitations page goes further than that. It bucketizes every eligible Traveler into one of three categories relative to the chosen Survey:

• New — the Traveler has never received an invitation to this survey.
• Reminder — previously invited but no completed response yet.
• Completed — already has a completed response on file.

You'll see counts for each bucket before you confirm the send. Reminders are opt-in (checked by default); re-sending to completed Travelers is opt-in (un-checked by default). You can never accidentally re-spam someone whose response is already in your analytics, no matter how many lists they happen to be on.

Opt-out works per Client, not per list

The unsubscribe link in every Survey Invitation flips a single flag on the Traveler Profile (travelers.dateOptedOut). After that, the Traveler is excluded from every future Survey Invitation you send — regardless of which list they're on or which survey you're sending.

This is a deliberate model choice and it matters for a few reasons:

• Compliance. CAN-SPAM and similar laws are written as "do not contact this person again," not "do not contact this person from this specific list." A per-list opt-out model would force you to track unsubscribes across lists yourself, which is exactly the kind of bookkeeping no agency wants to maintain.
• Trust. Travelers expect "unsubscribe" to mean "you won't hear from these people again." Honoring that expectation keeps your domain reputation healthy.
• Cross-survey signal. When a Traveler unsubscribes, it's almost never because of the specific list — it's because of the cadence, the relevance, or the survey design. Treating opt-out globally surfaces that signal honestly.

Note that opt-out only affects emailed Survey Invitations. An opted-out Traveler can still take a survey via a QR code or a direct link — they've told you not to email them, not "don't let me participate in research." For more on those entry points, see Three Ways to Invoke a Survey.

Importing a list: the header-aware CSV

CSV upload is the most common way to populate a list, and TIPS goes out of its way to make it forgiving. Two modes are supported:

1. Headerless / positional. Column 1 is the email, column 2 is the first name, column 3 is the last name, column 4 is the zip code. Only the email column is required.
2. Header-aware. If the first row contains a column whose name includes "mail", TIPS treats it as a header and maps columns by substring match. After that, column order doesn't matter at all.

The substring match is lenient. TIPS strips whitespace, underscores, hyphens, and dots from each header before comparing, so all of the following work:

• Email column — matches any header containing "mail". Email, E-Mail, email_address, Primary E.Mail all map to the email field.
• First name — matches "first", "fname", or "given". First Name, fname, given_name, FirstNm.
• Last name — matches "last", "lname", "family", or "sur". Last Name, LName, Family Name, Surname.
• Zip code — matches "zip" or "postal". Zip, Zip Code, ZipCode, Postal Code, postal_code.

If TIPS detects a header but can't find an email column, the upload is rejected up front with a clear error rather than silently misimporting. That's the only failure mode where the entire upload aborts — otherwise, individual row errors (malformed addresses) are dropped and counted.

What you'll see in the upload report

After the upload completes, TIPS shows you four counts:

• Added — new Traveler Profiles created.
• Matched — rows whose email already had a Traveler Profile for this Client. Name and zip on the existing profile are left as-is.
• Duplicates — rows whose email appeared more than once in the CSV itself, after the first occurrence.
• Invalid — rows where the email failed FILTER_VALIDATE_EMAIL. The CSV row number is logged so you can find and fix them.

A few patterns that work

1. One list per outreach campaign. Even if the people overlap with an existing list, a new list named for the campaign gives you a clean cohort for measuring response rates and tracking opt-out impact.
2. Re-upload, don't rebuild. If your source list in another system grows over time, re-upload the full CSV to the existing TIPS list rather than deleting and starting over. Existing Travelers are matched, new ones are added, opt-outs are preserved.
3. Use the manual add for a handful. If you have five new stakeholders, the manual-add form on the list page is faster than building a 5-row CSV.
4. Don't reuse old grant-survey lists for unrelated topics. A Traveler who agreed to participate in a corridor study did not sign up for your fare-policy survey six months later. Build a new list when the topic genuinely changes.

When verification matters, lists matter more

Every recipient on a Mailing List who completes a Survey Invitation becomes a verified response automatically — TIPS already knew the email before they ever clicked. That makes Mailing Lists the most efficient path to defensible, grant-quality response data. For the full mechanics of verification (and when to deliberately stay anonymous), see Understanding Verified vs. Anonymous Responses.

Common questions about Mailing Lists

Can the same email appear on more than one Mailing List?

Yes. A Traveler Profile is unique per (Client, email), but they can be on as many of your lists as you want. When you send a Survey Invitation that targets multiple overlapping lists, TIPS de-duplicates so the Traveler receives one invitation, not one per list.

How does opt-out work across lists?

Opt-out is per Client, not per list. If a Traveler unsubscribes from any of your Survey Invitations, they're opted out of all your future Survey Invitations — across every list they're on. The flag is stored on the Traveler Profile (dateOptedOut). They can still take a survey via QR code or direct link; opt-out only blocks emailed invitations.

What happens when I delete a Mailing List?

TIPS removes the list and its memberships. For each Traveler who was on it, TIPS deletes the Traveler Profile only if (a) they're on no other list of yours and (b) they have no survey responses. Travelers with responses are kept as "soft orphans" so your analytics history stays intact.

Does my CSV need a header row?

No, but a header row makes column order forgiving. If TIPS detects a header (it looks for a column whose name contains "mail"), columns can appear in any order — first name, email, zip, last name is fine. Without a header, TIPS reads positionally: column 1 = email, 2 = first name, 3 = last name, 4 = zip code.

What if my header column names are odd?

TIPS strips whitespace, underscores, hyphens, and dots before matching, then looks for substrings: "mail" anywhere → email; "first", "fname", or "given" → first name; "last", "lname", "family", or "sur" → last name; "zip" or "postal" → zip code. So "E-Mail Address", "given_name", and "Postal Code" all map correctly.

What happens to malformed email addresses in my CSV?

They're dropped during parsing (filter_var FILTER_VALIDATE_EMAIL) and counted in the upload report as "invalid". You'll see the count alongside "added" and "duplicate" so you can spot problems with the source list before sending.

Can I send a survey to multiple lists at once?

Yes. The Send Invitations page lets you pick multiple lists for the same Survey. Travelers on more than one selected list receive exactly one invitation. Reminder and re-send filters apply across the union, so you're never accidentally double-mailing someone.

Should I keep one giant list or many small ones?

Many smaller lists, generally. Smaller, intent-named lists ("Route 47 riders", "Downtown employers", "Public meeting attendees") give you more control over who receives which survey, make opt-out signals interpretable, and let you measure response rates per segment. TIPS handles the de-duplication so overlap isn't a cost.