SMTP for solar leads, and for roofing, window and HVAC lead-gen alongside it, is prohibited on Mailchimp, restricted on SendGrid, Brevo and Klaviyo, and allowed on Amazon SES only to addresses that consented to hear from you. Every shared ESP files homeowner lead-gen under affiliate marketing, because aggregator leads are resold 5 to 10 times and complain at 0.5% to 2%, far over Gmail's 0.3% limit. A dedicated SMTP server removes the provider policy. It does not remove CAN-SPAM, the FTC's deception rules on savings claims, or state contractor licence disclosure, and it does not make a 60-day-old aggregator lead open your email.
I've moved a handful of installers after termination notices. The story is always the same: aggregator calculator leads mailed like an opt-in list, dead account inside six weeks.
Which providers allow smtp for solar leads
Ask in writing before you pay, and ask about the nurture stream specifically. "Restricted" means a review on the first complaint spike, and it normally ends with promotional sending paused while your appointment confirmations sit in the same queue.
| Provider | Solar and home-improvement lead-gen | Notes |
|---|---|---|
| Mailchimp | Prohibited | Lead-gen and affiliate sending banned, co-registration lists named as a violation |
| Klaviyo | Restricted | Built for ecommerce, lead-gen accounts reviewed and often refused |
| SendGrid | Restricted | Quote and appointment mail tolerated, nurture to aggregator leads declined |
| Brevo | Restricted | Review required, list provenance checked |
| Amazon SES | Allowed if consented | Production access review, whole account pauses on complaint spikes |
| Mailgun | Case by case | Transactional favoured, promotional reviewed |
| Dedicated SMTP | Your own policy | IPs are yours, the law and receiver rules still apply |
The shape is identical to insurance lead-gen and affiliate email marketing: the transactional slice passes everywhere, the promotional slice to bought leads is what closes the account.
Why ESPs treat home-improvement as affiliate traffic
Three things make this category expensive on a shared IP, whether or not your business is legitimate.
Aggregator resale. A homeowner fills in a "how much can I save" calculator and the aggregator sells that record to 5 to 10 installers at once. Each buyer's automation fires within minutes. The homeowner remembers one form and finds eight companies in their inbox, and the fourth or fifth message gets reported. Shared aggregator leads complain at 0.5% to 2%. Exclusive leads behave better, but the consent form still names the aggregator.
Co-registration. A ticked box on a sweepstakes or survey page distributes the address to 20 advertisers. These lists complain at the top of that range and bounce at 8% to 15%.
Regulatory noise. Solar has a specific reputation problem. The FTC and Kentucky's attorney general sued Solar Titan USA in 2023 over misleading savings and rebate claims, and the FTC's 2024 impersonation rule covers "government program" language. A provider hosting a solar mailer is hosting claims it cannot check, so it restricts the category rather than audit it.
Gmail's bulk sender guidelines set a 0.3% complaint ceiling with 0.1% as the target, and an aggregator list breaks that inside the first send.
Compliance that a dedicated server does not remove
Moving to your own IPs takes the provider out of the picture. The law stays.
| Requirement | Applies to | What it demands | Exposure |
|---|---|---|---|
| CAN-SPAM | All US commercial email | Accurate From and subject, postal address, opt-out honoured within 10 business days, ad identified | $53,088 per email |
| FTC deception rules | Savings, rebate, tax-credit, "free" claims | Substantiation for the specific home, no implied government affiliation | Civil penalties, consumer redress, state AG suits |
| State contractor licensing | Roofing, HVAC, solar, windows in most states | Licence number on advertising in California, Florida, Arizona and others | Fines, licence suspension, unenforceable contracts |
| GDPR and PECR | EU and UK installers | Consent naming your company before marketing email | Up to 4% of turnover, £17.5m in the UK |
| TCPA | Calls and texts, not email | Written consent for automated calls to leads | $500 to $1,500 per call |
CAN-SPAM is opt-out law. The FTC's compliance guide lists every requirement, and meeting it is the floor. A lead that never heard of you can be mailed legally and will still report you, and complaints, not lawsuits, close accounts.
FTC deception rules. The claims that draw enforcement in solar are the same ones that draw complaints: "eliminate your electric bill", "government pays for your panels", "30% rebate" stated as cash back when it is a non-refundable tax credit, and a "program ending this month" that never ends. Every savings figure needs a basis for that homeowner's roof and utility rate, or a clear "estimate, varies by home" qualifier. The same rules cover roofing "insurance pays for it" pitches and HVAC "utility rebate" claims.
Contractor licence disclosure. California's CSLB requires the licence number on all advertising, Florida and Arizona have equivalent rules, and several states extend it to email. Put the licence number in the footer next to the postal address.
GDPR for EU installers. A UK or German installer buying leads from a comparison site needs consent that named them at the point of collection. "Receive offers from our partners" does not qualify, and aggregator leads in the EU are almost never usable for marketing email.
Suppression. One opt-out list, fed by every stream and every lead source, checked before every send. When a homeowner unsubscribes from the roofing offer, they have unsubscribed from the solar offer too.
Lead age decides your complaint rate
The biggest lever in this category is lead age at first send. Intent decays in days, and complaint rate rises as intent falls.
| Lead age at first email | Open rate | Complaint rate | Verdict |
|---|---|---|---|
| Under 24 hours | 35% to 45% | ~0.05% | Mail it, sequence of 5 to 7 over a week |
| 1 to 7 days | 20% to 30% | 0.1% to 0.2% | Mail it, shorter sequence |
| 8 to 30 days | 8% to 15% | 0.3% to 0.5% | Over Gmail's limit, one message with a clear reason |
| 31 to 90 days | Under 8% | 0.5% to 1% | Only to leads that clicked before |
| Over 90 days | Under 3% | 1% to 2% | Suppress |
These ranges come from installer and roofing accounts I have watched, and they hold across the four trades. The line that matters is the 30-day row: from there on, a lead's complaint rate alone fails Gmail's 0.3% threshold. Shops that keep mailing 6-month-old calculator leads are the reason the category is restricted.
The fix is operational, not technical. First quote email inside 5 minutes of the form. Sequence done inside 7 days. Monthly touch until day 90 for leads that clicked at least once. Then suppression.
Split appointment mail from nurture
An installer sends two kinds of email with nothing in common except the domain. They belong on separate subdomains and IPs.
| Stream | Subdomain | Contains | Complaint tolerance |
|---|---|---|---|
| Appointment and quote | quotes.yourdomain.com | site-survey confirmations, quote PDFs, proposal signatures, install schedules, permit updates | under 0.02% |
| Nurture | offers.yourdomain.com | seasonal promotions, financing offers, referral asks, re-quotes for old leads | under 0.1% |
The quote stream is wanted mail; the homeowner booked the survey an hour ago and opens the confirmation at 60% or better. The nurture stream carries the entire risk. When a spring blast draws complaints, the damage stays on offers.yourdomain.com and the signed proposal still lands. Combined, one campaign can stop a $28,000 contract reaching the customer.
Give each subdomain its own DKIM selector, DMARC record and IP. A 3-IP starter maps cleanly: quotes, nurture, and one spare for a second trade or a warm-up lane. DNS layout is in subdomain vs root domain for email sending.
What works on dedicated infrastructure
Dedicated IPs, one per stream. Reputation is yours alone. No other customer's complaints land on you, which is why there is no category policy to fail.
Per-campaign subdomains for seasonal pushes. A spring solar push or pre-winter HVAC campaign to 200,000 addresses is the highest-risk send of the year. Run it from its own subdomain, so if it draws 0.4% complaints the reputation cost dies with the subdomain and the year-round offers domain stays clean.
Two-strike engagement suppression. Two consecutive campaigns with no open or click and the address leaves the nurture stream. On a typical installer database this removes 30% to 50% of addresses on the first pass, and those addresses generated most of the complaints and nearly all of the bounces.
Seasonal warm-up before spring. Solar and roofing volume can triple between February and April. Start warming in January, ramp roughly 30% every two days per IP, and be at target volume four weeks before the season opens. An IP that sat at 5,000 a day all winter and jumps to 60,000 in March gets throttled by Gmail and Microsoft the same week.
DMARC at enforcement. Solar brands get impersonated for "your rebate is waiting" phishing. Start at p=none, read reports for 2 to 4 weeks, then move to quarantine and reject.
Content. Dollar savings in the subject line, "final notice", "government program" and shortened links all score badly, and two of them are FTC problems. Use your own tracking domain, plain-text disclaimers, and the licence number in the footer.
What it costs at 250K and 1M a month
A shop buying 1,500 leads a day with a 6-email sequence is at 270,000 a month before any nurture, so price both tiers.
| Provider | 250K per month | 1M per month | Dedicated IP | Policy risk |
|---|---|---|---|---|
| Amazon SES | ~$25, ~$50 with IP | ~$100 + $24.95 per IP | add-on | review, pauses on spikes |
| SendGrid Pro | ~$249 | ~$700 to $1,500 | 1 on Pro | restricted |
| Mailgun Scale | ~$255 | ~$600 to $900 | 1 included | case by case |
| Brevo Business | ~$250 to $350 | ~$400 to $700 | add-on | restricted |
| Klaviyo | ~$700 by contact count | ~$2,000+ | not offered | restricted |
| Dedicated server | $549 one-time plus ~$30 to $80 hosting | same server, same price | 3 included | none from a provider |
Klaviyo bills by contact, and a lead database of 80,000 to 300,000 addresses is the shape it punishes hardest. SES is the cheapest line if someone owns warm-up and monitoring, but its automated review pauses the whole account on a complaint spike, appointment confirmations included. At 250K a month the dedicated server undercuts SendGrid within 3 months; at 1M it is the cheapest option by several hundred dollars a month. Full working in cost to send 250,000 emails per month.
What to do after a termination
- Export while you can. Suppression lists, bounce logs, complaint reports, DKIM keys. Access usually closes within 48 hours.
- Find the cause. Complaint rate over 0.1%, bounces over 5%, or the category itself.
- Check domain reputation. Google Postmaster Tools, domain and IP separately.
- Clean before moving. Drop hard bounces, leads over 90 days without a click, and every address whose consent form did not name your company.
- Rebuild on dedicated IPs. Fresh quotes and offers subdomains, SPF, DKIM, DMARC at
p=none, matching PTR. - Warm up over 4 to 8 weeks. Appointment mail first, then nurture to the last 30 days of leads, then the rest. Roughly 30% more every two days per IP.
- Fix the intake. Get your company named on the aggregator's consent form, or buy exclusive leads, or stop buying from that source. Nothing above this line holds without it.
Step 4 is the one people skip. An aggregator list that closed a SendGrid account will blacklist dedicated IPs just as fast, and the second time there is no provider to blame.
How BulkEmailSetup helps
We build dedicated SMTP infrastructure for senders in restricted categories: your own server, your own IPs, full SPF/DKIM/DMARC/PTR configuration, MTA tuning, bounce handling and a warm-up plan, with appointment mail and nurture separated onto their own subdomains and IPs from the first send.
No shared pool means no category policy weighing your sending against other customers. Meeting CAN-SPAM, the FTC's advertising rules and your state's licensing disclosure remains yours. Basic starts at $549 one-time, covering 1 SMTP server, 3 dedicated IPs, 25,000 emails/day and unlimited contacts. Higher tiers scale to 15 IPs and 200,000 emails/day. See pricing.
Frequently asked questions
Which SMTP providers allow solar lead generation email?
Mailchimp prohibits lead-gen and affiliate sending and closes accounts that mail aggregator or co-registration lists. SendGrid, Brevo and Klaviyo restrict the category and usually pause the nurture stream after the first complaint spike. Amazon SES carries lawful solar and home-improvement mail to consented addresses after a production review. A dedicated SMTP server applies only the law and receiver rules, since there is no shared pool to protect.
Why do solar leads bought from aggregators complain so much?
A homeowner who fills one solar calculator form is typically sold to 5 to 10 installers, and each of them emails and calls within the hour. By the third message the homeowner has no idea who you are and reports it as spam. Complaint rates on aggregator lists run 0.5% to 2%, against a Gmail hard limit of 0.3% and a target of 0.1%.
How quickly should I email a new solar or roofing lead?
Send the first quote email inside 5 minutes and finish the follow-up sequence inside 7 days. A lead under 24 hours old opens at 35% to 45% and complains at around 0.05%. The same lead at 30 days opens under 8% and complains at 0.3% or worse, which is already at Gmail's cut-off. Age leads out of nurture after 90 days without a click.
What does the FTC require in solar marketing email?
CAN-SPAM requires accurate headers, a physical postal address, an opt-out honoured within 10 business days, and the message identified as an ad. On top of that the FTC's deception rules apply to savings, rebate and tax-credit claims, and the FTC has sued solar sellers over 'free solar' and 'government program' language. A claim you cannot substantiate for the specific homeowner's roof and utility is a claim to leave out.
Should solar quote emails and nurture campaigns share one server?
One server is fine, one subdomain and IP is not. Put appointment confirmations and quote PDFs on quotes.yourdomain.com with its own IP, and seasonal offers on offers.yourdomain.com with its own IP. When a spring promo draws complaints the damage stays on the offers subdomain and the signed proposal still reaches the homeowner.
What does solar lead-gen email cost at 250,000 a month?
Amazon SES runs about $50 a month with a dedicated IP, SendGrid Pro about $249, Mailgun Scale about $255 and Klaviyo about $700 because it charges per contact. A dedicated server is $549 one-time plus $30 to $80 a month hosting, which undercuts SendGrid within 3 months. At 1M a month the dedicated server is the cheapest option by several hundred dollars a month.
My SendGrid account was closed for solar lead-gen. What now?
Export suppression lists, bounce logs and stats within 48 hours, then check Google Postmaster Tools for your domain reputation. Drop every lead older than 90 days without engagement and every address whose consent form did not name your company. Rebuild on dedicated IPs under fresh subdomains, warm up for 4 to 8 weeks starting with quote follow-up, and do not open a replacement account on the same domain.
