Halal Screening Apps Compared: Do Zoya, Islamicly and Musaffa Agree on the Same Stock?
No — they do not always agree, and that is the single most important thing a UK investor needs to understand before trusting any of them. Run one ambiguous stock through Zoya, Islamicly, Musaffa and the Wahed screener and you can get a clean "compliant" from one and a "doubtful" from another, because each app applies a different rulebook (AAOIFI vs Dow Jones vs MSCI). This guide shows you exactly why, with a real worked example, so you can pick the screener that matches your own standard.
The short answer first
All four apps screen a company against two layers: a business-activity screen (does the firm earn a meaningful share of revenue from alcohol, gambling, conventional banking, pork, adult content, etc.) and a set of financial ratios (how much interest-bearing debt, how much interest income, how much liquid/non-compliant assets). The business screen rarely causes disagreement. The financial ratios do — because the threshold numbers and the denominators differ between standards.
For a clearly halal stock (a debt-free engineering firm) or a clearly haram one (a brewery), every app will agree. The disagreement lives in the grey zone: companies sitting near the debt or impermissible-income limits. That grey zone is exactly where you most need a tool, and exactly where the tools diverge.
The four apps at a glance
Here is the feature and price landscape as of mid-2026. Prices below are typically quoted in US dollars because these are global apps; UK users pay the GBP equivalent at checkout, and VAT may apply. Always confirm the live price in the app store before subscribing.
| App | Screening standard | Free tier | Paid tier (approx.) | Auto purification? |
|---|---|---|---|---|
| Zoya | AAOIFI-based (with the firm's own shariah advisors) | Limited free searches per day; pass/fail status | ~US$100/yr (Premium) | Yes — purification calculator on Premium |
| Islamicly | Dow Jones Islamic Market (DJIM), data by IdealRatings | Subscription-only — no genuine free tier | Subscription (tiered) | Yes — calculates purification % from impermissible income |
| Musaffa | AAOIFI standards, reviewed by scholars incl. an AAOIFI board member | Limited free access; compliance rating | ~US$7.49–$36/month depending on tier | Yes — purification calculator built in |
| Wahed screener | AAOIFI methodology (quantitative auto-screen + manual qualitative on request) | Free app; browse 55,000+ stocks | ~US$9.99 per stock for a certified qualitative report | No automatic calculator — gives pass/fail; certification is per-stock paid |
Sources: app store listings and the providers' own sites for Zoya, Islamicly, Musaffa and Wahed (linked at the foot of this guide). Coverage figures: Musaffa cites 120,000+ stocks and 8,500+ ETFs; Wahed cites 55,000+ stocks; Islamicly cites 30,000+ stocks.
The crux: why the apps disagree
There is no single global "halal stock" standard. There are several respected ones, and the screeners pick different ones. The three you will meet are:
1. AAOIFI (used by Zoya, Musaffa, Wahed)
The Accounting and Auditing Organization for Islamic Financial Institutions, based in Bahrain. It is generally the most conservative mainstream standard. Its core financial screens are:
- Interest-bearing debt must be below 30% of market capitalisation.
- Interest-bearing investments / cash below 30% of market cap.
- Impermissible (non-compliant) income below 5% of total revenue.
2. Dow Jones Islamic Market / DJIM (used by Islamicly)
Maintained by S&P Dow Jones Indices and used by a large share of institutional Islamic funds. It is slightly more permissive on the debt line:
- Total debt below 33% of the trailing 24-month average market capitalisation.
- Cash plus interest-bearing securities below 33% on the same denominator.
- Impermissible income capped at 5% of revenue.
3. MSCI Islamic (the methodology behind many index ETFs)
Not a consumer app, but the standard sitting behind a lot of the halal ETFs UK investors buy. Its key difference is the denominator:
- Total debt below 33.33% of total assets (not market cap).
- Cash and interest-bearing securities below 33.33% of total assets.
- Accounts receivable below 33.33% of total assets.
- Impermissible income below 5%.
Worked example: running "Aisha's stock" through all four
Let's make this concrete. Meet Aisha, a 34-year-old NHS pharmacist in Leeds. She wants to add a single mid-cap technology company — call it Helix Systems plc — to her Stocks & Shares ISA. She opens each app and types the ticker. Here are Helix's figures, taken from its latest annual report:
| Helix Systems plc — financials | Figure |
|---|---|
| Market capitalisation | £4.0 billion |
| Total assets | £2.2 billion |
| Interest-bearing debt | £700 million |
| Interest income (e.g. on cash deposits) | £9.6 million |
| Total revenue | £240 million |
| Core business | Enterprise software (clearly permissible activity) |
The business screen. Enterprise software — no alcohol, gambling, conventional finance, pork or adult content. All four apps clear this layer. Now the maths, where they split.
Step 1 — Impermissible income (the one line they all agree on).
Interest income ÷ total revenue = £9.6m ÷ £240m = 4.0%.
That is below the 5% limit every standard uses, so Helix passes the income screen everywhere. (Aisha will still need to "purify" that 4% of any dividend she receives — see below.)
Step 2 — The debt screen, AAOIFI (Zoya, Musaffa, Wahed).
Debt ÷ market cap = £700m ÷ £4,000m = 17.5%.
Comfortably under AAOIFI's 30% ceiling. Verdict: COMPLIANT.
Step 3 — The debt screen, DJIM (Islamicly).
Same debt over a 24-month average market cap. Suppose Helix's share price ran up sharply this year, so its 24-month average market cap is only £3.1bn.
£700m ÷ £3,100m = 22.6%.
Still under DJIM's 33% line. Verdict: COMPLIANT — but you can see the ratio has moved a lot just from changing the denominator.
Step 4 — The MSCI lens (the ETF you might buy instead).
Debt ÷ total assets = £700m ÷ £2,200m = 31.8%.
That is under MSCI's 33.33% line — but only just. Verdict: MARGINAL PASS. A year of extra borrowing or a fall in assets would tip Helix over, and the same company that looked safe at 17.5% on AAOIFI now looks borderline.
The lesson: Helix is a "clean" pass for Aisha on Zoya, Musaffa and Wahed (17.5%), a comfortable pass on Islamicly (22.6%), and a knife-edge pass on an MSCI-based ETF (31.8%) — all from the same accounts. Had Helix carried £800m of debt instead of £700m, the AAOIFI ratio would be 20% (still fine) but the MSCI ratio would be 36.4% — a fail. That is precisely the grey-zone split where two faithful investors, using two reputable apps, end up disagreeing.
Purification: which apps actually do it for you
Passing the screen is not the end. If a compliant company earns a small slice of impermissible income (Helix's 4%), classical scholarship says the corresponding slice of your dividends should be given away to charity — not kept. This is "purification" (tathir). It does not apply to your capital gain when you sell; it applies to dividend income.
Here is where the apps genuinely differ in usefulness:
- Zoya (Premium), Musaffa and Islamicly include an automatic purification calculator. You enter your dividend (or holding), and the app tells you the pounds to donate.
- The Wahed screener gives you a pass/fail/qualitative verdict but does not auto-calculate a per-holding purification figure for you — you would compute it yourself from the impermissible-income percentage.
Aisha buys 500 Helix shares and receives a dividend of £180 over the year. Helix's impermissible income ratio is 4.0%.
Amount to purify = £180 × 4.0% = £7.20 to give to charity.
She keeps the other £172.80. A premium app does this arithmetic automatically every time a dividend lands; with Wahed she would do it by hand. Note: because the dividend sits inside her ISA it is income-tax-free under UK rules — purification is a religious obligation, separate from tax.
What this means inside a UK ISA
For most UK Muslim investors, the screener is only half the job — the wrapper matters too. A Stocks & Shares ISA lets you hold individual shares and ETFs, and for the 2026 to 2027 tax year you can pay in up to £20,000 across your ISAs (gov.uk: Individual Savings Accounts).
Inside an ISA, dividends are completely tax-free — you "do not pay tax on dividends from shares in an ISA" (gov.uk: Tax on dividends). Outside an ISA, only the first £500 of dividends is tax-free in 2026/27; above that, dividends are taxed at 10.75% (basic rate), 35.75% (higher rate) or 39.35% (additional rate) — the ordinary and upper rates each rose by 2 percentage points from April 2026 (announced at the November 2025 Budget). So the screener tells you whether a stock is permissible; the ISA decides how much of the return you keep.
- Apps disagree in the grey zone, not the obvious cases. Clear halal and clear haram stocks pass/fail everywhere; near-threshold companies split.
- The disagreement comes from the rulebook. AAOIFI (30% of market cap) is strictest; DJIM (33% of 24-month avg market cap) and MSCI (33.33% of total assets) are more permissive — and use different denominators.
- Pick your standard first, then your app. Want the most conservative answer? Choose an AAOIFI app (Zoya, Musaffa, Wahed). Want to match the big index ETFs? DJIM/MSCI logic is more relevant.
- If you take dividends, you want auto-purification. Zoya Premium, Musaffa and Islamicly calculate it; the Wahed screener does not.
- For most UK investors: a free or low-cost AAOIFI screener plus a Stocks & Shares ISA (£20,000 allowance, tax-free dividends) covers the essentials. Pay up only when you hold many dividend-paying stocks and want automatic purification and portfolio-wide screening.
- Cross-check borderline stocks in two apps. If a holding sits near a threshold, a second opinion is cheap insurance.
So which app should a UK investor actually pay for?
There is no universal winner — it depends on what you hold and which standard you follow:
- You're starting out, US/UK blue-chips, few holdings: the free Wahed screener (AAOIFI, 55,000+ stocks) or Zoya's free searches will usually answer your question for £0.
- You take regular dividends and want purification done for you: Zoya Premium (~US$100/yr, AAOIFI) or Musaffa (from ~US$7.49/month, AAOIFI, deepest global coverage).
- You invest in non-US markets or want to match institutional DJIM funds: Islamicly (DJIM via IdealRatings) or Musaffa for its 120,000+ stock, multi-exchange coverage.
- You want a one-off certified, manually-reviewed verdict on a single contentious stock: Wahed's ~US$9.99 per-stock qualitative report.
Whatever you choose, treat the app as a tool, not a fatwa. The verdict is only as sound as the standard behind it — and for genuinely contentious holdings, a qualified scholar's view trumps any algorithm.
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Frequently asked questions
Can Zoya, Islamicly and Musaffa give different verdicts on the same stock?
Yes. They use different screening standards — Zoya and Musaffa follow AAOIFI, while Islamicly follows the Dow Jones Islamic Market (DJIM) methodology. For a clearly halal or clearly haram company they will agree. For companies sitting close to the debt or impermissible-income thresholds, they can disagree because the limits (30% vs 33%) and the denominators (market cap vs total assets) differ.
Which halal screening standard is the strictest?
AAOIFI is generally the most conservative of the mainstream standards. It caps interest-bearing debt at 30% of market capitalisation, versus 33% for DJIM and 33.33% of total assets for MSCI. All three cap impermissible income at 5% of revenue. If you want the most cautious answer, choose an AAOIFI-based app (Zoya, Musaffa or the Wahed screener).
Do all the apps calculate purification for me automatically?
No. Zoya (on its Premium tier), Musaffa and Islamicly include an automatic purification calculator that tells you how much of your dividend to give to charity. The free Wahed screener gives a pass/fail verdict but does not auto-calculate a per-holding purification figure — you would work it out yourself by multiplying your dividend by the company's impermissible-income percentage.
Is there a genuinely free halal stock screener?
The Wahed screener is a free app covering 55,000+ stocks on AAOIFI methodology, and Zoya offers a limited number of free searches. For unlimited screening, portfolio-wide checks and purification calculators you generally need a paid plan (Zoya Premium around US$100/year, Musaffa from around US$7.49/month). Many UK investors are well served by the free tools alone.
Are dividends from halal stocks taxed inside a UK ISA?
No. Dividends from shares held in a Stocks & Shares ISA are completely tax-free, per gov.uk. Outside an ISA, the first £500 of dividends is tax-free in the 2026/27 tax year, and above that they are taxed at 10.75%, 35.75% or 39.35% depending on your income tax band. Purification (giving away the impermissible slice of a dividend) is a separate religious obligation and is not a tax.
Should I trust the app's verdict completely?
Treat it as a tool, not a final religious ruling. The verdict is only as reliable as the standard behind it and the freshness of the financial data. For borderline stocks, cross-check in a second app, and for genuinely contentious holdings consult a qualified scholar. Compliance can also change as a company's debt or income changes, so re-screen periodically.