How to Read a Proxy Provider SLA Before You Sign

Most SLAs run a few pages. Read them in this order, not top to bottom, and write down one sentence per step.

1. Incorporation. Is this SLA referenced in the terms or order form you are signing? If not, stop: it is marketing.
2. Covered service. Which products and plans does it name? Trials, entry plans and add-ons are often out of scope.
3. Definition of unavailability. What exactly has to fail, for how long, before a minute counts as down?
4. Measurement. Whose monitoring decides, from where, at what interval?
5. Exclusions. Which failures do not count, and could your most likely outage fall into one of them?
6. Remedy. The credit percentage per tier, what it is a percentage of, and the cap.
7. Claim process. Deadline, required evidence, and whether credits are automatic.
8. Sole remedy and liability. Whether credits replace every other right you might have.

If you can write all eight sentences, you understand the SLA better than most people who signed it.

Proxy providers publish reliability promises in several places, and they do not carry equal weight.

Look for incorporation language in the terms, something that says the service level agreement published at a given URL forms part of the agreement. Then look for the amendment clause. Many terms let the provider change linked policies by updating the page, sometimes with notice and sometimes without. An SLA the provider can rewrite next month without telling you is a weaker promise than it looks.

On self-serve plans you usually get the public version as written. On enterprise contracts, ask for the SLA as a schedule in the signed document, so a later web edit does not change your deal. Our enterprise proxy procurement checklist covers the rest of that paperwork.

This is the clause that decides whether your outage counts. For proxies, "available" can mean very different things, and each level down the list is a stronger promise.

Nearly every proxy SLA stops at one of the first three rows. That is reasonable: no provider controls whether a website decides to block its ranges. But it means a day where every one of your requests returns a captcha can be 100% uptime by contract.

Read the definition for three proxy-specific details:

• Scope within the service. Does an outage of one port, one protocol or one country count, or only a full gateway outage? If SOCKS5 on its own port is down while HTTP works, is that downtime for a customer who only uses SOCKS5?
• Minimum duration. Some definitions only count an interval as down after several consecutive failed checks. Short, frequent failures can then add up to real pain and zero SLA minutes.
• Degraded service. Slow is not down. If latency triples, the SLA almost never applies unless it defines a performance threshold, which few proxy SLAs do.

A definition is only as good as its measurement method. Look for these answers in the text:

• Whose monitoring counts. Usually the provider's. Some SLAs accept customer evidence as supporting material; few let it override the provider's own records.
• Check interval. A check every minute catches outages that a check every five minutes misses. If the interval is not stated, ask.
• Measurement location. A monitor inside the provider's network can see a healthy gateway while customers on other networks cannot reach it.
• Period. Almost always a calendar month. A six-hour outage on the 3rd and a clean rest of month is averaged across roughly 43,200 minutes.
• Status page relationship. If the SLA says incidents must appear on the status page to count, the provider decides what counts.

None of these are unusual or sinister. They are simply where the headline number gets its shape, and they are the questions to put in writing before you sign.

Every SLA has an exclusions clause. The standard ones are fine. The proxy-specific ones can quietly cover the outages you are most likely to have.

Two patterns deserve extra care. First, emergency maintenance with no definition can swallow nearly any incident. Second, suspension exclusions interact with how aggressive the provider's abuse detection is: if an automated system suspends a legitimate account for a false positive, the resulting downtime may be excluded. That makes the suspension process in the terms at least as important as the uptime figure.

If blocklisting is your real risk, SLA credits will not solve it. How IP blacklisting works explains what to ask a provider about rotation and replacement instead.

Service credits are the SLA's only teeth, and they are usually small. Work out the number before you rely on it.

A useful reference for what a mature published SLA looks like is Amazon's EC2 compute SLA (last updated May 25, 2022, per the AWS page as of September 2026). Its region-level tiers credit 10% below 99.99% monthly uptime, 30% below 99.0%, and 100% below 95.0%. It counts unavailable minutes in the month, requires credit requests by the end of the second billing cycle after the incident, and states that the SLA is the sole and exclusive remedy. Many proxy SLAs follow a similar shape with different numbers, or with fewer tiers.

Now apply a tiered structure to a proxy bill. This is an illustrative example, not any provider's terms: a 99.9% SLA, 10% credit below 99.9%, 25% below 99.0%, 50% below 95.0%, on a $440 monthly plan.

Hold those figures against what the outage cost you. If a two-hour gap misses a nightly price collection that a client pays for, $44 does not touch it. That is why credit percentages matter less than two other lines:

• What the percentage applies to. The affected product's monthly fee, the whole invoice, or just the prorated days? A credit on one add-on is not a credit on your bill.
• The cap. Many SLAs cap total credits in a month, commonly at some share of the monthly fee. Once you hit it, further downtime costs the provider nothing.

Credits usually apply against future invoices, not as refunds. If you are leaving because of the outage, a credit on a bill you will never receive is worth zero. Check whether the terms allow termination after repeated SLA breaches, and read the refund policy alongside it. We compared those policies in proxy free trials and refund policies.

Many credits go unclaimed because the process requires something the customer did not collect. Read for four details: whether credits are automatic or must be requested, the deadline, the evidence required, and who to send it to.

Build your evidence before you need it. A minimal monitor that checks the gateway every minute from your own infrastructure gives you timestamps that line up with the provider's measurement period. Check two endpoints so you can tell a proxy failure from a failure of the test site itself.

# SLA evidence logger: one line per minute per endpoint, UTC timestamps.
import csv, time, datetime as dt
import requests

PROXY = "http://USER:PASS@gateway.sparkproxy.io:11000"
ENDPOINTS = ["https://api.ipify.org", "https://www.cloudflare.com/cdn-cgi/trace"]

def check(url, via_proxy):
    proxies = {"http": PROXY, "https": PROXY} if via_proxy else None
    try:
        r = requests.get(url, proxies=proxies, timeout=15)
        return r.status_code, round(r.elapsed.total_seconds(), 3), ""
    except requests.RequestException as exc:
        return 0, None, type(exc).__name__   # ProxyError, ConnectTimeout, etc.

with open("sla_evidence.csv", "a", newline="") as fh:
    out = csv.writer(fh)
    while True:
        minute = dt.datetime.now(dt.timezone.utc).strftime("%Y-%m-%dT%H:%M")
        for url in ENDPOINTS:
            out.writerow([minute, url, "proxy", *check(url, True)])
        out.writerow([minute, ENDPOINTS[0], "direct", *check(ENDPOINTS[0], False)])
        fh.flush()
        time.sleep(60)

At month end, count a minute as down only when both endpoints failed through the proxy while a direct request from the same host succeeded. That filter removes your own network problems and single-site outages, which is exactly what the provider's exclusions will do to your claim anyway. The error class matters too: a ProxyError with a 407 points at authentication, a connect timeout at the gateway. For more on building checks that separate proxy failure from target failure, see how to test if your proxy is working.

Set a calendar reminder for the claim deadline on the day an incident happens. A deadline of "within 30 days" passes quickly when you are busy fixing the outage.

For most proxy buyers, the worst days are not uptime incidents. They are account and capacity problems that no SLA touches. Read these clauses in the terms with the same care.

A provider with a modest SLA and clear, fair terms on the rows above is often a safer choice than one with an impressive percentage and vague suspension rights.

The phrases below are illustrative patterns, not quotes from any specific provider. Each one is legal and sometimes justified. Each one should prompt a question before you sign.

A provider that answers these clearly and in writing is telling you something good about how it operates. One that cannot answer is telling you something too. Our guide on spotting a fake proxy provider covers the more serious warning signs.

Bargaining power depends on spend and contract length. Be realistic about which requests land.

• Self-serve monthly plans: expect the published terms as written. Your real choice is picking a provider whose public terms already fit, and keeping monthly billing so you can leave.
• Larger annual commitments: reasonable asks include the SLA attached as a signed schedule, notice before policy changes apply to you, a written confirmation of your use case under the AUP, and a named escalation contact.
• Enterprise contracts: you may be able to negotiate a termination right after repeated breaches, a higher credit cap, a defined emergency maintenance limit, and IP replacement commitments for dedicated addresses.

Whatever the size, protect your operation with architecture rather than paper. A second provider on a different network, routed so a switch is a configuration change, recovers far more value in an outage than any credit. Proxy failover and redundancy covers how to set that up. Measure the provider's real performance on your own traffic too: how to measure proxy success rate is the metric that SLAs never cover.

Run the same eight-sentence read on SparkProxy's terms as on anyone else's. A few things are published and plannable today. Plans are flat monthly with unlimited bandwidth and 30-day validity: Starter $75 for 100 threads, Core $140 for 250, Boost $240 for 500 and Plus $440 for 1,000. The Fair Usage Policy publishes speed ceilings per plan (25, 50, 100 and 150 Mbps on those four, 200 and 250 on the unpriced Pro and Pro+ tiers, up to 1 Gbps on custom arrangements), and those are ceilings rather than guaranteed rates, which is the kind of distinction this guide asks you to look for.

The network is datacenter only, 1M+ IPs across 80+ countries on gateway.sparkproxy.io (port 11000 rotating, 11002 sticky, 13000 SOCKS5). If a clause in our terms is unclear to you, ask support@sparkproxy.io and get the answer in writing, exactly as you would with any other provider.