Best practices for importing contact lists into Handwrytten for large scale outreach

If you’re managing a big outreach campaign and want to mail hundreds or thousands of handwritten notes, getting your contact list into Handwrytten can seem like a headache waiting to happen. This guide is for the folks who actually have to wrangle the spreadsheet, not just nod on a Zoom call about “personalization.” Whether you’re in sales, fundraising, or client retention, here’s how to get your lists into Handwrytten with less pain, fewer surprises, and better results.

Step 1: Get Your List in Shape Before You Even Think About Importing

You can’t polish a turd, and you can’t rescue a bad contact list with software. Before you touch Handwrytten, open up your spreadsheet and do some honest cleanup.

What to actually do:

  • Stick to the essentials: Name, address (split by street, city, state, zip), and any merge fields you’ll actually use—like “Donation Amount” or “Favorite Color.” Don’t import fluff you don’t plan to use.
  • No mixed columns: Don’t cram “Bob Smith, 123 Main St, Apt 4” in a single cell. Break it out: First Name, Last Name, Address 1, Address 2, City, State, Zip, Country.
  • Ditch junk data: Delete contacts with missing addresses, obviously fake info, or “test” entries. If you wouldn’t mail it, don’t import it.
  • Consistent formatting: States as “NY” not “New York.” Zip codes as 5 digits (or 9 if you must). Watch for trailing spaces—those will bite you later.

Pro tip: Run a quick pivot table or deduplication pass. Handwrytten won’t magic away duplicates. If you send two cards to the same person, it just looks sloppy.

Step 2: Save as CSV—Not Excel, Not Google Sheets

Handwrytten wants a CSV file. Not an XLSX, not a Numbers file, not a Google Sheet link.

Why?
CSV is the boring, universal option that plays nice everywhere. If you upload something else, you’ll either get an error or—worse—something will break silently.

How:

  • In Excel or Google Sheets, choose “File > Download As > Comma Separated Values (.csv)”
  • Double-check your file: Open it in a plain text editor to make sure it’s not full of weird characters or extra commas.

Got special characters?
If you have accents, umlauts, or non-English names, save as UTF-8 CSV. Otherwise, you might end up sending a letter to “Jos� L�pez.” Not a good look.

Step 3: Match Handwrytten’s Required Fields—Don’t Guess

Handwrytten expects certain column headers. If you get these wrong, your import will fail or—worse—put data in the wrong place.

The must-haves:

  • First Name
  • Last Name
  • Address 1
  • Address 2 (optional)
  • City
  • State
  • Zip
  • Country (always use “US” or the correct 2-letter code)

If you want to use merge fields in your messages:
Add columns with short, clear headers like DonationAmount or CompanyName. Don’t use spaces or weird symbols. You’ll reference these when you write your template.

What not to do:

  • Don’t include columns you’re not using. More columns mean more things to go wrong.
  • Don’t improvise header names. “Zip Code” and “ZIP” are not the same to a computer.
  • Don’t mix address formats. Pick one and stick to it.

Step 4: Run a Test Import with a Tiny List

Don’t learn the hard way with 10,000 records. Pick 5-10 real entries (with actual addresses you can check) and do a test import.

Why bother?

  • You’ll spot issues like wrong columns, mangled characters, or missing data before they affect your whole list.
  • You can see exactly how your merge fields show up in the final message.
  • You’ll know if Handwrytten is going to choke on any part of your data.

How:

  1. Copy a handful of rows into a new CSV file.
  2. Import into Handwrytten.
  3. Preview your messages and addresses.
  4. Fix any issues in the main file before scaling up.

Pro tip: Use your own address and a colleague’s for the test, so you can see the finished product in your mailbox.

Step 5: Import and Map Your Fields—Don’t Rush

Now’s the time to upload your cleaned CSV to Handwrytten. The platform will ask you to match your columns to their fields.

What matters here:

  • Double-check every mapping. Don’t let “Address 2” end up as “City.”
  • If something doesn’t map, go back and fix your CSV—don’t try to fudge it in the UI.
  • Check the preview. If anything looks weird now, it’ll look weird on 5,000 postcards.

If you use merge fields:
Make sure each one is mapped and appears correctly in your message template. “Dear [First Name]” only works if [First Name] is mapped right.

Common mistakes to avoid:

  • Importing the wrong file (triple-check the filename; it happens).
  • Skipping the preview step.
  • Assuming “it worked last time, so it’ll work now.” Always check.

Step 6: Review, Filter, and Segment Before You Hit Send

You’ve imported your list, but that doesn’t mean you should send to everyone in it. Large-scale outreach is about quality, not just quantity.

What to do:

  • Filter by segment: Use Handwrytten’s filtering to split by region, customer type, or whatever makes sense for your campaign.
  • Spot check random entries: Read a few at random. If you see “Dear ,” or a missing address, fix it.
  • Remove obvious mistakes: Don’t send to people who unsubscribed, opted out, or said “stop mailing me.” If you’re not sure, leave them out.

Pro tip: Segmenting your outreach (e.g., different messages for donors vs. prospects) always beats blasting the same card to everyone.

Step 7: Expect Some Bounces—That’s Reality

No matter how carefully you prep, some addresses will be bad. Handwrytten will usually flag undeliverable mail, but not always.

  • Don’t obsess over 100% deliverability. The USPS isn’t perfect, and neither is your list.
  • After your first big send, look at the bounce/failure reports. Purge or update those bad addresses for next time.
  • If you’re mailing internationally, double-check country codes and address formats—international mail gets lost even more easily.

Step 8: Keep a Master List—Don’t Use Handwrytten as Your Database

Handwrytten is great at sending cards, but it’s not your CRM. Don’t treat it as the “source of truth” for your contacts.

  • Always keep a master version of your list in Google Sheets, Excel, or your CRM.
  • Track who you’ve messaged, when, and with what content—outside of Handwrytten.
  • Update your master list with any bounced addresses or changes after each campaign.

Why?
If you rely on Handwrytten alone, you’ll eventually lose track of who got what, miss unsubscribes, or mix up your segments.

Step 9: Iterate—Don’t Overcomplicate It

Once you’ve gone through the process once, it gets easier. Don’t try to build the perfect system from day one.

  • Start with a clean, simple list and a basic message.
  • Add more segments, merge fields, or personalization as you get the hang of it.
  • Don’t get sucked into “analysis paralysis.” Most mistakes can be fixed next time around.

Honest Takes: What Works, What Doesn’t, and What to Ignore

What actually works:

  • A tight, clean CSV file with only the data you need.
  • Short, clear merge fields.
  • Test runs with your own address.
  • Keeping your own master list.

What doesn’t:

  • Uploading bloated spreadsheets with extra columns.
  • Hoping Handwrytten will automatically fix formatting issues.
  • Using Handwrytten as your only contact database.

Ignore this advice at your own risk:

  • “Just export from Salesforce and upload.” (Don’t. Clean it first.)
  • “It’s fine if a few addresses are old.” (It’s not. It just wastes money.)
  • “Personalization isn’t worth the trouble.” (It is—if you do it right.)

Take a breath. Importing big lists into Handwrytten isn’t rocket science, but it does reward a little prep and some skepticism. Keep your lists simple, test before you scale, and don’t reinvent the wheel each time. Iterate, improve, and you’ll spend more time connecting—and less time cleaning up messes.