Quick answer: The parts that move fastest for most repair shops are the ones tied to the highest-volume faults: screens, batteries, and charging ports for the most commonly-owned phone models in your area — not necessarily the newest flagship. Stocking decisions should follow your actual repair ticket data and the active installed base of phones in your local market, not global sales rankings, which measure new-phone purchases rather than repair demand.
Why global sales rankings are the wrong input for stocking decisions
It's tempting to look at which phones are selling best right now and stock parts accordingly, but repair demand and new-device sales are different curves that peak at different times. A phone that's a top seller today won't generate meaningful repair volume for 12–24 months, once enough units are out of warranty and old enough to develop battery degradation, cracked screens, and worn charging ports. Meanwhile, a phone that peaked in sales three years ago is often still your highest-volume repair category today, simply because there are more of them in daily use, out of warranty, and past the point where owners baby them.
The practical implication: stock for the installed base you actually see coming through your door, not for whatever's newest. Your own repair ticket history is a better predictor of next quarter's demand than any industry sales chart.
The core stock list: what generates the most repair tickets
| Category | Why it's high-volume | Stocking priority |
|---|---|---|
| Screens (LCD and OLED, by model) | The single most common physical damage fault across all phone types | Highest — stock 2-3 grades per popular model |
| Batteries | Every phone's battery degrades eventually; this is a near-guaranteed repeat category | Highest — especially for phones 2+ years old |
| Charging ports / flex cables | High-frequency mechanical wear point | High |
| Back glass / housings | Common drop damage, especially on glass-backed flagships | Medium-high |
| Camera lens glass | Very cheap part, very common minor damage, fast turnaround job | Medium — low cost per unit makes overstocking low-risk |
| Speakers and microphones | Common after liquid exposure or general wear | Medium |
| SIM card trays | Frequently lost or bent; extremely cheap to stock | Medium — near-zero holding cost |
| Adhesives and seals | Needed for nearly every screen and battery job | High — you'll use these constantly regardless of model |
| Repair tools | Consumed/worn through regular use, not model-specific | Medium — keep spares on hand |
A simple inventory formula for repair shops
Rather than guessing at quantities, use your actual ticket history:
Reorder quantity = (average weekly units used for that part × supplier lead time in weeks) + safety stock
For a part you fit 3 times a week, from a supplier with a 1-week lead time, and you want a 1-week safety buffer: (3 × 1) + 3 = 6 units on hand before you need to reorder. This scales down naturally for slow-moving, model-specific parts — you don't need six units of a screen for a phone you only see once a month, but you do want enough buffer that a single unexpected job doesn't leave you unable to complete a same-day repair.
Real parts available for stocking, by category
Charging ports (fast-moving across brands):
- iPhone 16 charging port flex cable — from £14.99
- Samsung Galaxy S24 Ultra charging port board — from £16.99
- Samsung Galaxy A01 charging port board — from £4.99
Screens across grades:
- iPhone 14 FHD LCD screen — from £18.99
- Samsung Galaxy A36 OLED screen with frame — from £46.99
Low-cost, high-turnover parts worth keeping well-stocked:
- iPhone 13 Pro camera lens glass — from £1.99
- Battery adhesive strips — from £1.99
- 10-in-1 repair tool kit — from £0.99
Browse the full model-by-model ranges in our iPhone parts and Samsung screen replacement collections, or get in touch to discuss trade pricing and account terms for regular ordering volumes.
Seasonal demand patterns worth planning around
Repair demand isn't flat across the year, and stocking ahead of predictable peaks avoids the worst turnaround delays:
- Post-Christmas and New Year: new phones given as gifts mean older devices get handed down or sold on, often after a quick screen or battery fix first. Screen and battery demand for mid-range and older models tends to rise in January.
- Summer months: increased outdoor activity, swimming, and travel correlate with more liquid-damage and charging-port repairs (sand and moisture ingress), plus more drop-damage screen repairs generally.
- Back-to-school period: a secondary bump in screen and battery repairs as students prepare devices for the new term, often on hand-me-down phones rather than new purchases.
- Major manufacturer launch events: when a new flagship launches, expect a short-term dip in repair demand for the outgoing flagship as some owners upgrade rather than repair, offset by a rise in demand for trade-in-prep repairs (people fixing a phone specifically to get a better trade-in value before switching).
None of these patterns are large enough to justify dramatically overstocking ahead of time, but they're worth factoring into your reorder timing so you're not caught short during a predictable demand bump.
What to look for in a parts supplier relationship
Beyond unit price, a few factors matter more for repair shop operations than for individual consumer buyers:
- Consistent lead times. A supplier who's occasionally cheaper but unpredictably slow costs you more in missed same-day turnaround promises than the unit savings are worth.
- Clear grading and return policy on faulty stock. At volume, you will occasionally receive a defective unit — know exactly how returns and replacements work before you're relying on it under time pressure.
- Ability to order across multiple brands from one place. Consolidating iPhone, Samsung, and other Android parts sourcing reduces the number of supplier relationships and shipping schedules you need to manage.
- Willingness to discuss account terms for regular ordering volumes. If you're ordering consistently, it's always worth asking directly about trade pricing or account terms rather than assuming standard retail pricing is your only option.
How to identify your own highest-value stock categories
- Pull your last 90 days of completed repair tickets and group them by part category and model.
- Rank by frequency, not by revenue. A part you fit weekly at a modest margin is often more valuable to stock than a rare high-margin repair, purely because it keeps turnaround times fast and customers happy.
- Cross-reference against your local demographic. A shop in an area with a lot of budget Android users will have a very different stock priority list to one serving mostly iPhone owners — don't copy a generic list without checking it against your actual customer base.
- Flag anything you've had to turn away or delay due to lack of stock over the past quarter — these are your clearest signals for what to add or increase.
- Review quarterly, not annually. Phone popularity and typical fault ages shift meaningfully within a year — what mattered last January may not matter as much this January.
Balancing model-specific stock against low-cost universal parts
Not every stocking decision needs to be model-specific. Adhesives, screwdriver sets, opening tools, and SIM trays cost very little to hold in reasonable quantity and are used across nearly every job, regardless of which phone model walks through the door. Model-specific screens and batteries carry more holding-cost risk if a particular model turns out to be less common in your area than expected, so it's worth being more conservative with initial order quantities on new or less-established models until your own ticket data confirms demand.
Managing cash tied up in inventory
Every unit sitting on a shelf is capital you can't use elsewhere, and phone parts inventory has a specific risk profile worth understanding: model-specific parts (screens, batteries, charging ports for a particular device) can become slow-moving or effectively dead stock if that model turns out to be less common in your area than expected, or if a newer, cheaper part supersedes it. Universal consumables (adhesives, tools, small hardware) rarely go to waste since they're used across every job regardless of model.
A practical approach: weight your inventory investment toward universal consumables and your top 5-10 confirmed high-frequency models, and treat any expansion into less-certain models as a small, deliberate test rather than a large upfront commitment. Track sell-through rate by SKU, not just by category — two screens for different models at the same price point can have very different turnover speeds, and that's the number that actually tells you where your capital is working hardest.
How many models is realistic to stock for?
This depends heavily on your shop's size and customer volume, but a useful way to think about it is the 80/20 pattern that shows up in most repair shops' ticket data: a relatively small number of models — typically the two or three most recent generations from the top two or three brands in your area — account for the large majority of repair volume. Beyond that core list, it's usually more efficient to order on a per-job basis for less common models with a fast-shipping supplier, rather than holding stock for every possible device you might see. Trying to stock deeply for every model that exists ties up capital in parts that may sit for months, when that same money could fund deeper stock on your actual core models.
Frequently asked questions
Should I stock parts for the newest flagship phones first?
Not immediately — new flagships generate very little repair demand in their first year, since most units are still under warranty and haven't accumulated enough wear for battery or charging port issues. Prioritise phones that are 1-3 years old and known to be popular in your specific market.
How much safety stock should I keep for fast-moving parts?
This depends on your supplier's lead time and how disruptive a stockout would be to your turnaround promises. A good starting point is enough stock to cover your average weekly usage during your longest expected reorder wait, plus a small buffer for unexpected demand spikes — adjust based on your own experience over a few reorder cycles.
Is it worth stocking budget aftermarket parts alongside premium grades?
Often yes, if your customer base includes price-sensitive buyers — offering a genuine choice between a budget and premium repair, clearly explained, tends to convert better than a single price point. Just make sure your team can clearly explain the difference in quality and warranty to customers at the point of quote.
How do I avoid overstocking on a model that turns out to be low-demand in my area?
Start with small initial order quantities on any model you're not already confident about, and use your first month or two of actual sell-through as the real data point for reordering — rather than committing to a large initial stock based on national or global popularity figures alone.
What's the biggest inventory mistake repair shops make?
Stocking based on what's newest or most talked-about rather than what's actually walking through the door. The phones generating headlines are rarely the phones generating your repair tickets — your own data is a far more reliable guide than industry trend coverage.
Should I stock universal or model-specific tools?
Universal, wherever possible. Screwdriver sets, opening tools, and teardown kits are used across nearly every repair regardless of brand or model, so they carry very little of the model-specific dead-stock risk that screens and batteries do. Keep several sets on hand since tools wear out and occasionally go missing during busy periods.
Summary
Stock for the phones people actually bring in, not the phones dominating sales headlines — repair demand lags new-device sales by roughly a year or two, and your own ticket history is the most reliable data source you have. Prioritise screens, batteries, and charging ports for your highest-frequency models, keep universal low-cost consumables like adhesives and tools well-stocked regardless of model, and review your stocking priorities quarterly against your actual sell-through data. Treat any expansion beyond your core models as a deliberate, small-scale test rather than a large upfront bet, and let real sell-through — not assumptions — decide what earns a permanent place on your shelf.