Fix it yourself first

1. Restart first. Turn airplane mode on for 10 seconds, then off. If that doesn't help, restart the phone. This fixes more "slow data" than everything else combined.

2. Test it properly, don't guess. Use two free tools: fast.com and speedtest.net (both work in your web browser, no app needed). One test proves nothing. Test three times: morning, evening rush (6-9pm), and late night, and write the numbers down.

3. Separate Wi-Fi from cellular. Run the tests twice: once on your home Wi-Fi and once with Wi-Fi turned off. Slow on Wi-Fi only? The problem is your home internet or router (restart the router), not your phone plan. Slow on cellular only? Read on.

4. Know the speed game. If cellular is fast at midnight but crawls at 7pm, you're likely being deprioritized: carriers slow down cheaper plans and budget brands when towers are busy. That's not a broken phone, and no setting fixes it: it's how your plan was designed. If it happens daily, a plan with priority data (or a different network) fixes it, and that's exactly what our comparison accounts for.

5. Also check: some "unlimited" plans slow you down after a monthly amount (look for "premium data" or a GB threshold on your plan page), and video is often deliberately limited to DVD quality unless you pay more.

You almost certainly don't need a new phone. Storage-full warnings sell more phones than any advertisement, and it's usually just photos and videos.

1. Move photos to the cloud. iPhone: Settings → your name → iCloud → Photos, turn on "Optimize iPhone Storage" (50GB is about $1/month). Android: install Google Photos, turn on backup, then use its "Free up space" button (100GB is about $2/month). Your photos stay viewable on the phone; the full-size copies live safely online, protected even if you lose the phone.

2. Clear the other hogs. Delete old text-message attachments (Settings → General → iPhone Storage, or Files by Google on Android; both show what's eating space and offer one-tap cleanups), remove apps you haven't opened in a year, and delete downloaded videos in streaming apps.

The math: cloud storage costs $12-36 a year. A new phone costs $600-1,200. If storage is the only problem, that's the whole decision.

1. Turn on Wi-Fi Calling. The single best fix for weak signal indoors: your calls route over your home internet instead of the distant tower. iPhone: Settings → Cellular (or Apps → Phone) → Wi-Fi Calling. Android: Settings → search "Wi-Fi Calling". It's free and most people have never heard of it.

2. Restart, then reset network settings if the problem started suddenly (Settings → General → Reset → Reset Network Settings on iPhone; note you'll re-enter Wi-Fi passwords).

3. If it's always been bad at your address, it's the network, not the phone. Different carriers use different towers: a neighbor on another network may have full bars. Coverage in your ZIP is one of the main things our comparison weighs.

Pull up your bill (the PDF, not the summary) and look for these, in order:

1. Autopay discount missing. Advertised prices almost always assume autopay ($5-10/line). If you pay manually, you pay more. Some carriers only give the discount for bank account or debit autopay, not credit cards.

2. Taxes and fees. Some carriers include them in the advertised price; the big ones usually don't, so expect $3-8/line extra. Nothing to fix, but now you know why "$65" is $73.

3. An expired promotion. Intro prices quietly end after 12 months, trade-in credits stop if you change plans, and "free line" promos have conditions. Compare this month's bill to one from six months ago, line by line.

4. Add-ons you didn't ask for. Device insurance, premium voicemail, entertainment bundles, often added at the store "free for the first month." Cancel anything you don't recognize.

If self-help didn't solve it, call prepared: the person answering is often paid to sell, not to fix.

Have ready: your account number, the last bill PDF, your speed test numbers (with times), and the exact dates any problem started.

Say what you want, specifically. Not "my phone is slow" but: "My download speed at my home ZIP drops below 2 Mbps every evening. I've tested it on three days and restarted the phone. I want a network ticket opened, or a credit."

Write down the representative's name and ask for a reference number for the call. If they promise a credit or a price, ask them to send it in writing (text or email) before you hang up.

Decline the upsell in the moment. Whatever new plan or device is offered as "the fix," say you'll consider it and check it against an independent comparison first. That's literally what we're here for.

If you get nowhere: ask for the retention department (they have more power), and know that the FCC complaint form (fcc.gov/complaints) is free and carriers respond to it quickly.