How to Set Up a Drip Campaign with SendGrid + Twilio (Step-by-Step)

You don't need an all-in-one platform to run sophisticated drip campaigns. You need the right providers and a way to connect them.

SendGrid handles email delivery for over 80 billion emails per month. Twilio processes billions of SMS messages. Both offer developer-friendly APIs, pay-as-you-go pricing, and deliverability infrastructure that rivals (or outperforms) what bundled marketing platforms provide under the hood.

The catch? Neither one is designed to orchestrate a full drip campaign on its own. SendGrid can send emails on a schedule. Twilio can fire off an SMS. But building a multi-step, multi-channel sequence, where an email goes out on day 1, a follow-up SMS on day 3, a conditional branch on day 7 based on who opened what, requires either custom code or an orchestration layer that ties both services together.

This guide walks you through both approaches: the manual setup for teams comfortable with code, and the no-code path using a BYOA (Bring Your Own Account) platform that connects directly to your existing SendGrid and Twilio accounts.

Before building your first drip campaign, you'll need three things in place:

1. A SendGrid account with a verified sender. If you don't have one yet, sign up at sendgrid.com. The free tier gives you 100 emails per day, enough for testing. For production campaigns, their Essentials plan starts at $19.95/month for 50,000 emails. Once your account is active, you'll need to complete sender authentication (domain verification via DNS records) to protect your deliverability.

2. A Twilio account with a registered phone number. Sign up at twilio.com. Twilio's trial gives you a test number and $15 in credits. For production SMS campaigns in the US, you'll need to register for A2P 10DLC (Application-to-Person 10-Digit Long Code), this is a carrier-mandated compliance step that verifies your business and your messaging use case. Plan for 10–15 days for campaign approval.

3. A subscriber list with proper consent. Both email and SMS require opt-in consent. For email, this means your subscribers actively signed up to receive marketing messages from you. For SMS, consent requirements are stricter, you need explicit written consent (a checkbox or form submission), and every SMS must include opt-out instructions. Don't skip this. CAN-SPAM governs email; TCPA and carrier policies govern SMS. Violations are expensive.

Authentication is the foundation of deliverability. Skip this step and your emails will land in spam and your texts may be filtered by carriers.

Domain authentication tells inbox providers (Gmail, Outlook, Yahoo) that SendGrid is authorized to send email on behalf of your domain. This involves adding three DNS records:

• SPF (Sender Policy Framework) — authorizes SendGrid's servers to send from your domain
• DKIM (DomainKeys Identified Mail) — adds a cryptographic signature to every email so recipients can verify it wasn't tampered with
• DMARC — tells inbox providers what to do with emails that fail SPF/DKIM checks (quarantine or reject them)

In the SendGrid dashboard, navigate to Settings → Sender Authentication → Authenticate Your Domain. SendGrid will generate the DNS records you need to add at your domain registrar (Cloudflare, Namecheap, Route 53, etc.). Once the records propagate (usually within a few hours), SendGrid will verify them and your domain is authenticated.

This is a one-time setup. Every email you send through SendGrid going forward will carry your authentication, which improves inbox placement over time as you build sender reputation.

For US-based SMS campaigns, carriers require A2P 10DLC registration. This is a three-part process:

1. Brand registration — You submit your business details (legal name, EIN, address) through the Twilio Console under Messaging → Trust Hub. Twilio verifies your business identity.
2. Campaign registration — You describe your messaging use case (marketing, notifications, etc.), provide sample messages, and confirm your opt-in/opt-out process.
3. Number assignment — Once approved, you associate your Twilio phone number with your registered campaign via a Messaging Service.

Start this process early. Carrier reviews currently take 10–15 days, and you can't send production SMS marketing messages until approval is complete. Use the waiting period to build your email templates and plan your drip sequence.

Before you touch any tools, map out your campaign on paper (or a whiteboard, or a doc, whatever works). A drip sequence has three components:

The trigger: What event starts the sequence? Common triggers include a new subscriber joining your list, a purchase, a free trial signup, or a form submission.

The cadence: How many messages, over what timeframe, with what delays between each? A typical welcome sequence might look like:

The exit conditions: When should someone leave the sequence? If they make a purchase, unsubscribe, or reply to an SMS opting out, they should be removed automatically. Define these conditions before you build, not after.

Resist the urge to blast both channels simultaneously. Email and SMS serve different roles in a drip campaign. Email is for longer-form content, educational material, detailed product information, stories. SMS is for short, high-urgency messages, a quick reminder, a time-sensitive offer, or a personal check-in that feels more like a text from a colleague than a marketing message.

The sweet spot for most SMB drip campaigns is 70–80% email and 20–30% SMS. Overusing SMS will spike your costs (you're paying per message) and your unsubscribe rates (people are protective of their text inbox).

SendGrid offers two template creation paths: a visual drag-and-drop editor and an HTML code editor. For drip campaigns, the visual editor is usually sufficient and significantly faster.

Navigate to Email API → Dynamic Templates in the SendGrid dashboard. Create a new template for each email in your sequence. A few best practices:

Use dynamic fields for personalization. SendGrid supports Handlebars syntax for personalization. Insert {{first_name}}, {{company_name}}, or any custom field from your contact data. Personalized subject lines consistently outperform generic ones, this isn't optional anymore, it's baseline.

Keep the design simple. For drip campaigns, plain-text-style emails (minimal formatting, no heavy graphics) often outperform heavily designed newsletters. They feel more personal, load faster, and are less likely to trigger spam filters. Use a clean single-column layout with your brand colors and a clear CTA.

Include an unsubscribe link in every email. SendGrid handles this automatically if you use their substitution tags, but verify it's there. CAN-SPAM requires it, and inbox providers use its presence (or absence) as a deliverability signal.

Name your templates with a consistent convention. Something like "Welcome Series — Email 1 — Welcome," "Welcome Series — Email 2 — Quick Win" makes it easy to manage as your campaigns grow.

SMS messages don't need templates in the traditional sense, they're short text strings. But they do need planning.

Keep messages under 160 characters when possible. SMS messages over 160 characters are split into multiple segments, and each segment is billed separately. A 170-character message costs you the price of two messages. Write tight.

Always identify your brand. Carrier regulations require that marketing SMS messages identify the sender. Start with your brand name: "Drip Drop: Hey {{first_name}}, quick tip for your first automation..." This also builds recognition so recipients don't wonder who's texting them.

Include an opt-out instruction. Every marketing SMS must include a way to stop receiving messages. "Reply STOP to unsubscribe" is the standard. Twilio's Messaging Service handles STOP/HELP keywords automatically if configured correctly.

Use Twilio's link shortening for any URLs. Long URLs eat into your 160-character budget and can trigger carrier spam filters. Twilio's Programmable Messaging API supports link shortening with click tracking, so you get a branded short link and analytics on who clicked.

This is where your approach diverges based on your team's technical capabilities. You have two options: build the orchestration yourself with code, or use a BYOA platform that handles it for you.

If you have a developer on your team (or you are one), you can orchestrate a drip campaign using SendGrid's and Twilio's APIs directly. The basic architecture looks like this:

1. A subscriber database (PostgreSQL, MySQL, or even a structured spreadsheet for small lists) that stores contact info, subscription status, and where each contact is in the drip sequence.
2. A scheduling system that triggers the right message at the right time. This could be a cron job, a task queue (like Celery if you're in Python/Django), or a serverless function on AWS Lambda or Cloudflare Workers.
3. API calls to SendGrid and Twilio to send the actual messages when triggered.

Here's a simplified example of what the SendGrid API call looks like in Python:

import sendgrid
from sendgrid.helpers.mail import Mail

sg = sendgrid.SendGridAPIClient(api_key='YOUR_SENDGRID_API_KEY')

message = Mail(
    from_email='[email protected]',
    to_emails='[email protected]',
    subject='Welcome to Drip Drop',
)
message.template_id = 'd-your-dynamic-template-id'
message.dynamic_template_data = {
    'first_name': 'Sarah',
    'company_name': 'Acme Marketing'
}

response = sg.send(message)

And the Twilio SMS call:

from twilio.rest import Client

client = Client('YOUR_TWILIO_ACCOUNT_SID', 'YOUR_TWILIO_AUTH_TOKEN')

message = client.messages.create(
    body="Drip Drop: Hey Sarah, quick tip — your first automation can be live in under 10 min. Here's how: https://drfrp.co/quickstart Reply STOP to unsubscribe",
    from_='+1YOURTWILINUMBER',
    to='+1SUBSCRIBERNUMBER'
)

The upside of this approach: Total control. You own the code, the data, the timing, and the logic. No platform fees beyond what you pay SendGrid and Twilio directly.

The downside: You're building and maintaining a marketing automation engine from scratch. Handling edge cases (what if the API call fails? what if a subscriber changes status mid-sequence? how do you handle timezone-aware send times?) turns a weekend project into ongoing maintenance. You also don't get a visual workflow view, A/B testing, or analytics without building those too.

For a simple 3–5 email sequence that doesn't change often, the code approach is viable. For anything more complex, conditional branches, multi-channel coordination, dynamic segments, you'll outgrow it quickly.

A BYOA (Bring Your Own Account) platform lets you connect your existing SendGrid and Twilio accounts and build drip campaigns visually, without writing or maintaining code. The platform handles orchestration: sequencing, timing, conditional branching, A/B splits, and analytics. You keep your own provider accounts, your own sender reputation, and your own wholesale rates.

The setup looks like this:

1. Connect your SendGrid account by entering your API key. The platform uses SendGrid's API to send emails on your behalf, through your authenticated domain, on your IP reputation.
2. Connect your Twilio account by entering your Account SID and Auth Token. SMS messages are sent through your registered Twilio number, using your A2P 10DLC campaign.
3. Build your drip sequence in a visual drag-and-drop editor. Drag an email node, set a delay, add an SMS node, create a conditional branch ("if opened email 2 → send path A; if not → send path B"), and connect it all visually.
4. Import your contacts and map fields (email, phone, name, any custom attributes) to the platform's contact model.
5. Activate the workflow and monitor performance through unified analytics that combine email and SMS metrics in one dashboard.

The advantage isn't just convenience, it's that every message still flows through your infrastructure. You're not sharing SendGrid servers with thousands of other customers on a bundled platform. Your deliverability is your own, your data stays in accounts you control, and if you ever switch orchestration tools, your SendGrid and Twilio accounts come with you unchanged. (We wrote about why that distinction matters in our post on Mailchimp vs. BYOA.)

Never launch a drip campaign without testing the full sequence end-to-end. Here's a pre-launch checklist:

Send test emails to yourself and at least one other person. Check rendering across Gmail, Outlook, and Apple Mail—each handles HTML email differently. Verify that personalization fields populate correctly (not showing raw {{first_name}} tags).

Send test SMS messages to your own phone. Confirm the message displays correctly, the link works, the brand name is present, and the STOP keyword triggers an automatic opt-out response.

Test the timing. If your drip is set to send email 2 three days after email 1, test with a shortened delay (e.g., 5 minutes) to verify the sequencing logic works before committing to the real cadence.

Test the exit conditions. Subscribe a test contact, then simulate the exit event (mark them as purchased, unsubscribe them, have them reply STOP). Confirm they're removed from the sequence and don't receive the next message.

Check deliverability. After your test sends, log into the SendGrid dashboard and check the Activity Feed. Look for bounces, blocks, or deferrals. On the Twilio side, check message status in the Messaging Logs, confirm messages show "delivered," not "failed" or "undelivered."

Once your drip campaign is live, the work shifts from building to monitoring. Here's what to watch:

Email metrics (via SendGrid dashboard):

• Open rate — Aim for 30–50% on drip sequences (they typically outperform batch campaigns because they're triggered and timely). Note that Apple Mail Privacy Protection inflates open rates, so treat this as directional, not absolute.
• Click-through rate — 3–5% is solid for automated sequences. If clicks are low but opens are high, your email content or CTA needs work.
• Bounce rate — Keep this under 2%. Hard bounces should be removed from your list immediately. SendGrid handles this automatically if you're using their contact management.

SMS metrics (via Twilio dashboard):

• Delivery rate — Should be 95%+ for a clean list with proper A2P registration.
• Click-through rate (if using link shortening) — SMS CTRs are typically higher than email. 10–15% is a reasonable benchmark for marketing SMS.
• Opt-out rate — If this spikes above 3–5% per message, you're sending too frequently or the content isn't relevant. Dial back.

After the first 100 contacts complete the sequence: Review the data and optimize. Which email in the sequence has the lowest engagement? That's your weakest link, rewrite it or replace it. Is the SMS driving clicks, or are people ignoring it? Experiment with different messaging or a different position in the sequence. Are contacts dropping off at a specific point? The delay before that message might be too long (they've forgotten about you) or too short (they feel spammed).

One of the main advantages of using your own SendGrid and Twilio accounts, whether you orchestrate with code or a BYOA platform, is cost transparency. Here's what a typical drip campaign costs with this setup versus a bundled platform, assuming 5,000 contacts going through a 5-email + 1-SMS sequence:

At 5,000 contacts, the savings are meaningful. At 25,000 or 50,000 contacts, the gap widens significantly because your sending costs scale at wholesale rates while bundled platforms scale at marked-up rates. (For a full breakdown of how these costs stack up, see our guide to the true cost of marketing automation.)

Don't skip domain authentication. Sending emails through SendGrid without SPF, DKIM, and DMARC is like mailing a letter with no return address. Inbox providers will treat your messages with suspicion, and your deliverability will suffer from day one.

Don't send SMS without A2P registration. Unregistered 10DLC traffic in the US faces aggressive carrier filtering and rate limiting. Your messages may be silently dropped. Complete your A2P registration before you launch.

Don't overcomplicate your first campaign. Start with a straightforward 4–5 step linear sequence. Add conditional branches and A/B splits after you have baseline data on what's working. Complexity without data is just guessing with extra steps.

Don't treat email and SMS as interchangeable. An email CTA and an SMS CTA should be different even when they drive to the same destination. Email CTAs can afford explanation ("See how three companies used automated workflows to cut their campaign setup time by 60%"). SMS CTAs should be short and direct ("Quick setup guide → [link]").

Don't forget timezone awareness. An email sent at 9 AM Eastern arrives at 6 AM Pacific. A text message at 6 AM is not a good look. If your list spans multiple timezones, use send-time optimization to deliver messages during reasonable hours for each recipient.

Once your first drip campaign is running and generating data, you'll naturally want to expand. Here's where most SMBs go next:

Add conditional branching. Instead of sending every contact the same sequence, branch based on behavior: opened vs. didn't open, clicked vs. didn't click, purchased vs. still browsing. Each branch gets a message tailored to where the contact actually is in their decision process.

Build more sequences. Your welcome series is just the start. Consider re-engagement sequences (for subscribers who've gone quiet), post-purchase sequences (onboarding, upsell, referral), and event-based sequences (webinar follow-up, abandoned cart).

Layer in AI-powered optimization. Use send-time optimization to deliver messages when each individual subscriber is most likely to engage. Use AI to analyze which subject lines perform best across segments and automatically prioritize winners. (For practical tips on this, see our guide on using AI to write better marketing emails.)

The foundation you've built—authenticated SendGrid for email, registered Twilio for SMS, a clean subscriber list with proper consent, scales to support all of this. That's the real advantage of building on your own infrastructure: every improvement compounds on a foundation you own.

Drip Drop makes it easy to build multi-channel drip campaigns by connecting your own SendGrid and Twilio accounts to a visual drag-and-drop workflow builder. No code required, no sending markups, full control of your infrastructure. Sign up →